Microsoft has violated its own published user interface guidelines that it offers to designers. Ironically I cannot find the same version of these guidelines that I remember: they came out during the Vista beta program, and have since been edited and re-edited, and moved from place to place on the Microsoft web site. However, these guidelines were well stated and even seem to be based on our knowledge of human cognition.

The largest single region of the human brain is the cerebral cortex, which is tasked with parallel processing of large quantities of visual input. In contrast, our short-term memory is capable of holding only about seven pieces of information, and transfer of information into and out of this short-term memory is not always efficient.

Display All Options

The first interface design guideline I will discuss is that whenever possible the interface should show all options which are available to the user. For example, the Excel 2003 Format Axis > Patterns tab shows all axis tick options, allowing us to use our vast image processing capability, rather than load the options into short term memory:

In contrast, the Excel 2007 Format Axis > Axis Options dialog shows only the currently selected axis tick options. Sure, I “know” the other choices, because I have formatted hundreds of thousands of chart axes in my Excel experience. But I still have to stop to think what these options are, or click on each dropdown in turn to remind myself.

The dialog in 2007 is smaller than that in 2003, but it is not as self-explanatory, and isn’t the 2007 dialog larger anyway? (See below for an analysis of dialog sizes.)

Show Closely Related Subtasks Together

The second interface design guideline states that controls for tasks or subtasks that are done together should be placed in proximity to one another. My “good” example here is the Excel 2003 Format Series > Patterns dialog, which contains the options for Area (Fill) and Border for area, bar, and column charts, and the options for Marker and Line for line and XY charts. For an XY chart, for example, the controls for selecting markers, line styles, and colors appear on a single screen:

Excel 2007 provides a “bad” example for this guideline. The same options as above require the Excel 2007 user to jump between SIX different views: Marker Options, Marker Fill, Line Color, Line Style, Marker Line Color, and Marker Line Style. There is a lot of empty space on these six panes. When various preliminary options are made, this space fills with the various formatting options (gradients, fills, etc.) which were added to Excel 2007. These options would be more effectively added as child dialogs, as they are not used as much as “plain” formatting; in fact, many would say that their use runs contrary to good charting practice. Relegating fancy formatting to child dialogs would enable the separate items to be once again combined onto a single dialog view, and suppress the urge to add chart-junk formatting to charts.

Dialog Size

It is worth a brief digression to examine the old and new dialogs. The Excel 2007 chart formatting dialogs appear a lot larger then their 2003 predecessors, but the practical increase in size is mush smaller.

I’ve reduced the images of the dialogs to 66% of their original size, outlined the working region in red, and highlighted the dialog client area in yellow.

– - –

The Excel 2007 dialog is 20% larger than the 2003 dialog, and the client area (yellow) is 22% larger. However, the working area (red outline) is only 6% larger. Most of the increase in area is consumed by the “tabs”, which are compactly arranged in 2003 and displayed in a list in 2007 which fills at most half of the space given to the list. (So there is  plenty of room in the list to restore missing tabs, such as Error Bars and Data Labels.)

If the area of the 2003 dialog were made as large as that of the 2007 dialog by increasing its height, it would have 22% more space to accommodate enhanced formatting, not 6% for formatting and 16% for empty space.

– - –

Maximize Interactivity

The Excel 2003 Format Axis > Scale dialog is an elegant example of interactivity that makes a user’s job easy. Clicking the checkbox or its label changes the value of the cheeckbox. Clicking also changes focus to the box with the value and highlights the entire value, saving the user a click and drag. For example, I can change the minimum from 0 to 1 with two minor actions: click on the Minimum checkbox, then type 1. Also, the value entry boxes are always enabled, so I can click on one anytime. If I change one of the values and the checkbox is checked, it automatically unchecks itself.

One change in the 2007 version of the Axis Scale dialog may even be an improvement. Often inexperienced users would enter a desired axis scale value i the box above and then click Auto, which then told Excel to use its own value and ignore what the user entered. Giving the user a choice between Auto and Fixed may clarify the definition of “Auto” in this context.

The improvements end here, and the functionality is decreased. First, notice that the entry boxes are disabled if the Auto options are selected. This means the user cannot just highlight a value and overtype a new value to change to a fixed value. The user mush select Fixed first. Selecting Fixed, unlike in the 2003 version, does not give focus to the value entry box, nor select the current value. This forces more mouse actions on the user.

This lack of interactivitiy compared to the earlier version of the dialog indicates a few things to me. First, there was a lack of familiarity with the dialog among the design team. Second, there was a lack of resources to implement the dialog completely (which was evident during the technical preview phase). Another sign of a hastily implemented 2007 dialog is that the Fixed option buttons are all one pixel higher than the corresponding Auto option buttons.

Summary

My colleague Dennis has pointed out in a comment to Blue Ribbon Interface, my recent post summarizing user complaints about the Excel 2007 Ribbon interface, that this interface is version 1.0, and that we should expect improvements in version 2.0. I agree completely that the 2007 interface is not mature, though I consider it more of a 0.9 version.

I expect changes in the Ribbon, but I fear that other aspects of the interface design, such as dialogs which reduce productivity as much as or more than the Ribbon, will remain in version 0.9 in the next release of Office. The Ribbon is a new innovation, receives a great deal of attention, and will likely see a great deal of development. On the other hand, dialogs are an old technology, not considered worth deploying scarce resources to improve.

Author Robert Benchley once said, “The biggest obstacle to professional writing is the necessity for changing a typewriter ribbon.” The modern equivalent may be that the biggest obstacle to professional work in Office 2007 is an arbitrarily changing ribbon.

Simon Murphy has hosted a week’s worth of commentary about the Office UI Ribbon, aka the Office Fluent Interface. This last has been modified to Effluent Interface by its biggest “fans”. Simon uses the phrase frequently, and so do several of his readers, but I think I may have actually coined the term in a comment on Simon’s blog.

Simon has pulled no punches about this glaring new interface, and he attracts substantial commentary supporting and expanding on his views. Simon’s readers do not consist of ordinary crybabies; they include the most experienced and advanced Excel users on the planet, and these experts have opinions which should be heard.  Simon’s topics over the past week include:

• Ribbon lovers week
• Excel 2007 ate my work
• Ribbon Will it – won’t it control thingy
• Ribbon tab based litter
• Ribbon screen stealer
• Ribbon Style Princess
• The ribbon file blunderfest

Jimmy Pena covered the ribbon in his blog recently, in a post bemoaning the fact that Microsoft has had to release add-ins to help users find where their favorite 2003 commands have been hidden in 2007:

• Need Ribbon help? You’re not alone.

I’ve covered the ribbon in a few of my own blog entries:

• A Belated Review of Excel 2007
• Changes to Charting in Excel 2007
• What happened to my favorite Excel 2003 Chart feature?

I don’t totally hate the ribbon, in fact. It’s relatively easy to work with as a designer. The XML is relatively straightforward, and there’s a tremendous resource for dealing with the Office 2007 ribbon interface, RibbonX: Customizing the Office 2007 Ribbon, by Robert Martin, Ken Puls, and Teresa Hennig. It’s the book I use most often lately. It would be easier to work with custom ribbon layouts if you didn’t have to close the workbook containing the XML code to edit it, and if the editing tools were more fluid in their behavior. But you can in fact interface the ribbon with VBA, with a little effort.

As a user, however, I think the ribbon is a mistake. The ribbon has morphed into a variable toolbar with large, sparsely positioned buttons. Too few controls are available at a time, and too many are hidden arbitrarily, by the Microsoft philosophy that “These are the controls we know you need for what we know you want to do now”. There is no built-in way for the user to customize the ribbon and show the controls the user knows he wants for what he is actually doing, though third-party developers have tried to fill this gap. And the ribbon isn’t even the most frustrating part of the new interface. Many new dialogs have become awkward and unwieldy, requiring the work of one Excel 2003 dialog tab to be spread over two or more (in one case SIX!!) dialog tabs.

The program was designed to connect corresponding points of two XY series in a chart, with arrows pointing from the point in the first series to its partner in the second. Starting with a chart like this:

The program produces this effect in Excel 2003 and earlier.

Pretty cool.

Now run the same procedure on the same chart in Excel 2007, and the result is completely not what you expected. The arrows are all pointing straight downward, and not located near the points they are supposed to connect.

The culprit is the way VBA in Excel 2007 interprets these two lines of code:

    Xnode1 = Xleft + (mySrs1.XValues(Ipts) - Xmin) * Xwidth / (Xmax - Xmin)
    Ynode1 = Ytop + (Ymax - mySrs1.Values(Ipts)) * Yheight / (Ymax - Ymin)
 

These lines provide the X and Y coordinates of the point in the first series (the tail of the arrow), in pixels from the top left of the chart. MySrs1.Values(Ipts) correctly returns the Y value of the point, but MySrs1.XValues(Ipts) returns not the X value of the point, but the index of the point in the series, as text, not as a numeric value.

In the chart below, I have highlighted the sixth point in each series and the sixth arrow. We can see that the arrow points from the Y value of point 6 in the first series down to the Y value of point 6 in the second series, while the X value of both endpoints of the arrow is 6.

I can think of another way to create the desired arrows in Excel 2007, and when I have a chance I will write them up.

Stay tuned.

Update 3 June 2009

I discovered that if a chart only has one series, the lines of code above will return the correct X value, though it is still typed as a String.

Update 4 June 2009

On the suggestion of Andy Pope, I downloaded and installed SP2 (I had been using Excel 2007 SP1). As Andy indicates, the code from my earlier article runs fine. The proper X values are extracted from the series data, and they are even typed as doubles.

SP2 fixes the problem. Good job with the update, and sorry to have reported a problem that was already fixed.

I did find another bug, however. I wrote a little routine to spit out chart data into the worksheet, and I used

 With ActiveChart.Parent.TopLeftCell.Offset(, 9)
 

to locate the output of the routine. This works fine in Excel 2003. Excel 2007 SP2 chokes on the Offset method of the Range object, and the line above is highlighted in the debugger.

This works in 2003

 Dim rTopLeft As Range
 Set rTopLeft = ActiveChart.Parent.TopLeftCell
 With rTopLeft.Offset(, 9)
 

but the last line of the above still chokes on Offset. What finally works in 2007 is

With Range(ActiveChart.Parent.TopLeftCell.Address).Offset(, 9)
 

A little work in the Immediate Window shows that it’s TopLeftCell that has the problem.

Anyway, a blog reader emailed me with a problem. The LastPointLabel procedure seemed to run fine, but her chart didn’t show the labels. Could I look at it?

I discovered another of those little inconsistencies which will keep us programmers gainfully employed for years to come. These glitches are frustrating, but I guess if I sell myself as an Excel 2007 Incompatibility Expert, I could probably double my hourly rate. They also gives me plenty to blog about.

What happens in Excel 2007 is that, even though a point is not plotted because of a blank cell or #N/A error, the label is applied without an error. You can’t see it, because the point isn’t plotted. But if you put a valid number into the cell, the point and its label appear. This is actually a nice way to handle labels for unplottable points, but the fact that the behavior is different than that of earlier versions leads to loss of functionality of existing code.

The way around this is to examine the values of the series. In 2007 and 2003, if a cell is blank then the corresponding value of the array of series data is blank. In 2007, an #N/A error also leads to a blank in the data array, whereas in 2003, an #N/A error is represented by “Error 2042″, VBA-speak for the error.

In the corrected code below, the series data is inspected before an attempt is made to label the point. It’s actually more elegant in a way, because the code doesn’t rely on a failure before it does the right thing.

Sub LastPointLabel()
  Dim mySrs As Series
  Dim iPts As Long
  Dim vYVals As Variant
  Dim vXVals As Variant

  If ActiveChart Is Nothing Then
    MsgBox "Select a chart and try again.", vbExclamation
  Else
    Application.ScreenUpdating = False
    For Each mySrs In ActiveChart.SeriesCollection
      With mySrs
        vYVals = .Values
        vXVals = .XValues
        ' clear existing labels
        .HasDataLabels = False
        For iPts = .Points.Count To 1 Step -1
          If Not IsEmpty(vYVals(iPts)) And Not IsError(vYVals(iPts)) _
              And Not IsEmpty(vXVals(iPts)) And Not IsError(vXVals(iPts)) Then
            ' add label
            mySrs.Points(iPts).ApplyDataLabels _
                ShowSeriesName:=True, _
                ShowCategoryName:=False, ShowValue:=False, _
                AutoText:=True, LegendKey:=False
            Exit For
          End If
        Next
      End With
    Next
    ' legend is now unnecessary
    ActiveChart.HasLegend = False
    Application.ScreenUpdating = True
  End If
End Sub
 

If you’re not sure what to do with this code, please refer to my tutorial, How To Use Someone Else’s Macro.

Warning: This is a long post. It contains a lot of pictures though to keep you entertained, and near the end there’s a cool utility you can download and use for free.

Review of Error Bars in Classic Excel

It’s easy to add error bars in Excel 97 through 2003. Bring up the Format Series dialog, by double clicking on the series, by right clicking on the series and choosing Selected Object, by selecting the series and choosing Selected Data Series from the Format menu, or by selecting the series and clicking the shortcut, Ctrl+1 (numeral one). The dialog has a tab for Y Error Bars, and if it’s an XY data series, there is also a tab for X error bars.

From this dialog you can assign values to the error bars, such as a fixed value, a percentage of the data point value, a couple of statistical measures, and custom values from a worksheet range. You can also assign the direction of the error bars (plus, minus, both, or neither). One nice feature is that the custom error bar value selection controls are right on the same dialog as everything else.

To format error bars, you first select them, then bring up the dialog with a double click, a right click, the Ctrl+1 shortcut, or the Format menu. In the chart below I have clicked once, which selects both X and Y error bars in an XY chart.

The dialog has three tabs. Any changes you make on the Patterns tab affects both X and Y error bars.

The other two tabs allow you to reapply error bar values.

Rather than selecting both sets of error bars in this chart, I have clicked once to select both X and Y error bars, then again to reduce my selection to just the Y error bars.

The Format Error Bars dialog now only has a Patterns tab and a Y Error Bars tab. If you change any format on the Patterns tab it only affects the error bars you selected before opening the dialog.

Changes to Error Bars in Excel 2007

It is harder to apply error bars in Excel 2007. There is no convenient tab on the Format Series dialog. The Error Bar tab(s) as well as the tabs for Data Label, Up/Down Bars, High/Low Lines, and other features have been removed to make them more discoverable, at least that’s what we were told. To discover these features in Excel 2007, select the chart and navigate to the Chart Tools > Layout contextual tab. Click on the Error Bars button, and scratch your head while you try to decipher the options.

Finally, select the More Error Bars Options at the bottom of the list. X (if it’s an XY chart) and Y error bars are added to the chart series, with the Y error bars selected, and the Format Error Bars dialog is displayed with the Vertical Error Bars tab showing. (If the chart has more than one series, and you had not specifically selected one series, there is an intermediate dialog asking which series to work with.)

This dialog doesn’t look too unfamiliar. There is not obvious way to switch to the horizontal error bars. We are used to having two not just a tab for the vertical error bars, but also one for the horizontal error bars.

Hmm, oh yeah, modeless dialog. Click on the horizontal error bars, problem solved.

Unlike Excel 2003 and earlier, you cannot select both X and Y error bars in Excel 2007. This means that if you want the same formatting to both, you have to apply it twice, and the F4 function key shortcut for Repeat Last Action only repeats the last single itty bit of formatting (if you change line color, thickness, and dash type, for example, only dash type is repeated).

An inconvenient part of the user interface for error bars in Excel 2007 is that you need to click a button to enter custom error bar values, and this pops up a small dialog. This dialog is modal, so if the Format Error Bars dialog was partially covering the range you want to use, you have to clear the small child dialog, move the main dialog, and bring up the Custom Error Bars dialog again.

By default, each field contains a one element array with the element value equal to one. You can enter another constant value, and you don’t need to type the equals sign or curly brackets; Excel will insert them. More likely you want to select a range. Make sure you delete the entire contents of the entry box before selecting a range, or at least select it all, or Excel will think you meant to enter something like

={1}+Sheet1!$D$5:$D$13
 

If you want the value to be zero, enter zero. Don’t completely clear an entry box. because Excel will think you simply forgot and it will retain the previous value.

For all of the problems, using error bars in Excel 2007 isn’t completely terrible. You have some nice formatting options available to you. One that appeals to me is an alternative to the regular end cap appearance of the error bars.

You can change to the end-cap-less variation, then format the error bar line style so they end with an arrow head.

I don’t remember if this is the most useful, or the only useful, new formatting feature available in Excel 2007 charts.

Error Bar Utility

To make it easier to use error bars in Excel 2007 (and in Classic Excel), I’ve built a small utility, which you can download and use for free. It’s found in ErrorBars.zip. This zip file contains two versions, ErrorBars.xls for Excel 97 through 2003, and ErrorBars.xlam for Excel 2007. Install this utility by following the instructions in Installing an Excel Add-In or in Installing an Add-In in Excel 2007.

In Classic Excel, the utility places a new item, Add Error Bars, at the bottom of the chart series context menu. All you have to do is right click on the series and select Add Error Bars.

Despite all the assurances that context menus work the same in Excel 2007 as in earlier versions, you cannot add an item to an Excel 2007 chart-related context menu. What I’ve done instead is to add an Error Bars item to the end of each of the three Chart Tools contextual ribbon tabs. I know the new philosophy of Office is to place a command in only one place in the whole user interface. I prefer the old style philosophy, however, which is to place the command in every place it may be relevant. I never know where I may be when I want to use a command, and some people remember different hiding places than I do.

Whether in Excel 2007 or in earlier versions, click on the added command, and the utility behaves the same. Up pops a simple dialog with four data entry boxes, for plus and minus Y error bars, and for plus and minus X error bars.

If the chart type is not XY, the X error bar entry boxes are disabled.

You can select a range or enter a constant into the entry boxes.

I hope that this tutorial and the associated utility will make your life easier when working with error bars in Excel 2007.

The improvements to charts in Office Excel 2007 were dramatic. You can now create professional-looking charts with special effects, such as realistic 3-D, transparency, and soft shadows.

I’ll leave aside (for now) discussions of professional looks and realistic 3-D. But many of the other items deserve attention.

The article says, “Because of these changes, certain features that worked one way in Excel 2003, work differently in Excel 2007 or require alternative approaches to create similar results. Here’s an up-to-date summary of those Excel 2003 features that work differently in Excel 2007 and how to get those similar results.” The article tabulates these differences in a table of features, 97-2003 behavior, and 2007 behavior. I will use a similar format, using portions of the article text to describe features and behavior in 97-2003 and 2007, while adding my comments for each feature.

Feature: Simultaneous resizing of multiple charts

97-2003: You can change the size of multiple charts simultaneously.

2007: You must change the size of each chart individually.

Jon: The second item on the page, and it’s wrong. You can select multiple charts and resize them together, either with the mouse or with the Size group on the Drawing Tools > Format ribbon tab. In fact, this is actually easier in 2007, because the cursor changes when you mouse over the resizing handles. In 2003 the cursor doesn’t change, so you have to take it on faith that your actions will resize the charts.

What is confusing about Excel 2007 is that there is no difference in the appearance of a single chart which has been activated to format its elements and one or more charts which have been shift-click or ctrl-click selected for formatting of the parent shape that contains the chart. In 2003 and earlier, when the chart is activated, small black handles appear on the corners and edges of the chart. When the chart’s container object is selected, small white handles appear on its corners and edges. In 2007, no matter whether the chart is activated or the chart’s container is selected, the same awkward, thick border is displayed.

Feature: Using pattern fills in chart elements (for black-and-white printing and to improve readability for the visually-impaired)

97-2003: You can use pattern fills in chart elements.

2007: Instead of pattern fills in chart elements, you can use picture and texture fills. Charts with pattern fills that were created in an earlier version of Excel appear the same when they are opened in Excel 2007, but you cannot use the pattern fills in other chart elements.

Jon: Patterns are still available in VBA, and there are already at least two add-ins to add back this capability. Andy Pope has a nice Pattern Fill Add-In which applies fill patterns to chart elements and to shapes.

Feature: Sizing charts with the window

97-2003: You can use the Size with window command to automatically resize charts that are located on chart sheets when you change the size of the window.

2007: Instead of the Size with window command, you can use the Zoom to Selection command to achieve similar results.

Jon: Losing Size with Window removes a lot of critical functionality, including the ability to show full-window charts, and the ability to use mouse-position-based chart events on chart sheets. Zoom to Selection is a woefully inadequate substitute for Size with Window. I have had clients who could no longer use previously successful utilities because of this change to Excel 2007.

Feature: Copying charts to Microsoft Office Word 2007 and Microsoft Office PowerPoint 2007

97-2003: By default, a copied chart is pasted as a picture in an Office Word 2007 document or Office PowerPoint 2007 presentation.

2007: By default, a copied chart is pasted in an Office Word 2007 document or Office PowerPoint 2007 presentation as an object that is linked to the Excel chart. You can change the way that a copied chart is pasted by clicking the Paste Options button that is displayed when you paste the chart, and then pasting the chart as a picture or an entire workbook.

Jon: In Excel 2007, the pasted chart is inaccessible to VBA, regardless of the Paste Option used. You can regain the familiar OLE behavior and access the inserted Excel object in VBA if you insert the chart from a file.

Feature: Direct manipulation of data points on charts

97-2003: You can drag data points on a chart and change their source values on the worksheet.

2007: Dragging data points to change the source values on the worksheet is no longer supported.

Jon: I rarely used this feature, so I didn’t think it was a big deal to have it deprecated. I have to admit being surprised by how many users miss this feature.

Feature: Drag and drop data

97-2003: You can add data to a chart by selecting the data in the worksheet and dragging it onto the chart.

2007: You can no longer drag data from a worksheet to a chart. You can use other methods to add data to a chart.

Jon: This is no loss. It has always been more reliable to copy the data and use Paste Special to add the data to the chart. This still works fine in Excel 2007.

Feature: Built-in custom chart types

97-2003: Several built-in custom chart types are installed with Excel.

2007: There are no built-in custom chart types, however, you can easily create your own custom chart types, by saving your favorite charts as chart templates.

Jon: “Built-in custom”, one of my favorite oxymorons. The absence of these chart types is no big loss. In earlier versions of Excel, users discovered these types, and presumed that combination charts were limited to whatever they could find in this part of the Chart Type dialog. In general, it’s better in Excel 2003 to ignore these chart types, and make your own combination charts, because the custom built-in types may behave in unexpected ways when you change the chart’s source data range.

In fact, the absence of these chart types is a positive thing. Microsoft has changed the way users can save custom chart formatting. The Excel 2003 approach stored all of a user’s custom charts in a hidden user gallery workbook. This approach makes it difficult to share custom charts among users, and I’ve found this gallery workbook to be prone to corruption. The Excel 2007 technique saves each custom chart as a separate chart template file. These are more reliable, and can be shared between users (and I believe between Office applications).

Feature: Grouping and selecting shapes

97-2003: Shapes are drawn in a format that differs from the shape format that is used in Excel 2007.

2007: Shapes that are drawn in earlier versions of Excel cannot be grouped with shapes that are drawn in Excel 2007, even when the shapes are upgraded to the current version. You cannot select shapes that are created in different versions of Excel at the same time. Shapes that are created in different versions of Excel are layered on top of current shapes. To select the current charts, use the chart element selection box (Chart Tools, Format tab, Current Selection group). To select hidden charts or shapes that were created in an earlier version of Excel, you must first add the Select Multiple Objects command to the Quick Access Toolbar.

JP: Not only are shapes from different generations of Excel treated differently for grouping, they are also placed in different Z order positions. Adding a shape or picture, followed by

Set MyShape = ActiveSheet.Shapes(ActiveSheet.Shapes.Count)
 

may return a different shape than expected, breaking a lot of legacy code.

Feature: Record chart shapes and shape formatting in a macro

97-2003: You can record changes to chart shapes and formatting in a macro.

2007: You cannot record changes to chart shapes and formatting in a macro.

Jon: This is a severe loss in functionality. PowerPoint 2007 has it even worse: it has lost its macro recorder altogether.

Microsoft knowledge base article 937620, You cannot record new shapes, shape formatting, and shape effects by using the macro recorder in Excel 2007, states that “This behavior is by design.” I suspect it’s more a matter of triage, redeploying scarce resources to prepare Office 2007 for Release to Manufacturing. I can’t believe anyone would consciously redesign a serious product in this way.

The article suggests, “To work around this behavior, use Microsoft Visual Basic for Applications (VBA) code to format the shapes. In Visual Basic Editor, click Object Browser on the View menu to find the correct objects, methods, and properties that are used in VBA code.”

Hello? Has anybody tried to decipher the new object model branch related to formatting of the new shapes and chart elements? At least Young and Champollion had the Rosetta Stone. I find this new content in the Object Browser inscrutible and the examples less than useless. In the past, when the Object Browser was hard to interpret, one could at least record a macro to help resolve the syntax behind the object model.

Extended Summary

There have been a lot of changes to the charting infrastructure in Excel 2007. The highly touted formatting features are not an improvement, but a distraction (see Steven Few’s review in Excel’s New Charting Engine — Preview of an Opportunity Missed). I believe that these gaudy formatting options are partly responsible for the order-of-magnitude increase in chart redraw times (see Excel 2007 Chart Performance – Revisited).

A few of the changes to Excel 2007 charts are really an improvement (the new custom chart template feature), or at worst, neutral (built-in custom chart types, drag and drop data, resizing of multiple charts). The over-antialiasing of Excel 2007, which I have covered elsewhere, gets mixed reviews. I give it a thumbs down, but some respected commentors like it. A related issue, which I have not covered in detail but the PowerPoint FAQ website and several online forums have, is that a metafile produced from an Excel 2007 chart cannot be broken down into its constituent shapes the way an Excel 2003 chart can be.

A few of the changes to Excel 2007’s charts are actually detrimental. The way new and old shapes are treated, and the way pasted charts are accommodated in PowerPoint and Word, cause problems. Many users are hobbled by the removal of the ability to drag points on a chart to change the underlying data. Removing UI access to pattern fills was a small decrease in capabilities.

Two features covered here are particularly unfortunate. Losing the ability to size a chart with the active window was a surprising change, and has broken a number of existing routines. The inability to record formatting actions in a macro ties the hands of programmers who need to understand the changes to the object model, and users who are just trying to make their lives easier.

Removal of the familiar menu/toolbar user interface in favor of a new ribbon/tab interface has drawn a great deal of criticism. In principle the ribbon interface should be an improvement, but experienced users have had to retrain themselves in tasks that shouldn’t have to be relearned. A detriment of the new interface is the much lower density of controls visible at any time, and the inability to change the interface through the interface. (Yeah, I know, we have the QAT. But seriously.) Worse than the confusing triad of contextual chart tabs is the redesigned set of chart-related dialogs, which I covered in some detail in Changes to Charting in Excel 2007. And I wonder why it was decided to no longer open an object’s formatting dialog when that object is double clicked on, breaking well over a decade of user interface convention. The unintended consequences of these UI changes have made me much less productive when working with charts in Excel 2007.

I didn’t think I agreed with Jorge, but to be fair I singled out one of my files to take a closer look. I opened the file in Excel 2003 and exported a number of charts using my Enhanced Export Chart Procedure. Then I reopened the file in Excel 2007, and exported the same charts. I looked at the charts side by side, and I still prefer the Excel 2003 rendering.

Each of the following pairs of charts shows the 2003 chart above the 2007 chart.

The markers and lines of the 2007 chart series is fuzzy compared to the 2003 chart series. This is probably due to overaggressive antialiasing. I’d rather have the series appear crisp, even if the lines are more jagged/

This 2007 chart has a fuzzy chart series. In addition, the right edge of the chart has been truncated. This truncation is not an artifact of exporting the chart: it was present in the live chart as well.

Again, the 2007 chart series are fuzzy. Why should my charts make me feel that I need new eyeglasses?

Not only are the chart series in the 2007 chart blurry, the markers are larger than in the 2003 original, and the legend font has been somehow distorted.

Sorry, Jorge, we don’t see eye to eye. I do agree that creating and formatting charts in Excel 2003 is much easier. But I don’t think 2007 charts look any better than their 2003 counterparts. The data is blurred, the markers may be increased in size, the fonts may be distorted. Some spacing around the margins of the charts may be altered, usually inconsequentially, but occasionally resulting in cropping of chart elements.

Simon Murphy of Codematic and the Smurf on Spreadsheets blog wondered how much of the difference was related to chart redrawing itself, and how much was related to recalculation. To assess the difference, I fired up my two Virtual PC sessions, both running Windows XP SP2 with 1023 MB of RAM. One VM has Excel 2003 SP3 loaded, the other has Excel 2007 SP1.  I ran four tests in each version of Excel, all with 100 columns, and with 1000, 2000, 5000, and 10,000 rows (0.1, 0.2, 0.5, and 1.0 million cells). I used this command in the Immediate Window of the VB Editor:

debug.Print now, timer : for i=1 to 100 : activesheet.calculate : _
    next : debug.Print now, timer
 

This recalculates the sheet 100 times, outputting the time (date and time as well as elapsed seconds) before and after the recalc. The average recalc time consists of the difference in these times, divided by 100. The test results are available in Recalc2003v2007.csv. I summarized the data in the following pivot table.

The chart below clearly shows that recalculation in Excel 2007 is slower than in Excel 2003, taking anywhere from 23% to 32% longer.

While Excel 2007’s recalculation is slower than Excel 2003’s, the main effect slowing down chart redrawing in Excel 2007 is not due to the small difference in recalculation. The order of magnitude difference in chart redrawing must be related to the new Office shapes used to construct charts in Excel 2007.

I used Virtual PC to do my testing, using two virtual machines with Windows XP SP2 running in 513 MB, one with Excel 2003 SP3, the other with Excel 2007 SP1. Robert Kosara wondered whether using only 513 MB was strangling Excel 2007. I changed the settings on the two VMs so they each used 1023 MB, and I reran the tests.

Running in a larger memory space did help Excel 2007. The XY charts showed an improvement of 11-20% in redrawing time, while the line charts showed an improvement of 19-34%.

The larger memory also helped Excel 2003. The XY charts showed an improvement of 12-20% in redrawing time, while the line charts showed an improvement of 15-30%.
Excel 2007 is still about an order of magnitude slower than Excel 2003.

The test results can be read in ChtPerf2003v2007ram.csv. Here is the pivot table of the data.

Here is a comparison of 2003 and 2007 XY charts. Both versions of Excel experience an improvement with 1023 MB over 513 MB, but the ratios between 2007 and 2003 redrawing times are essentially unchanged.
With 1023 MB of RAM, the Excel 2007 XY charts take 8.5 to 11 times as long to redraw as the Excel 2003 XY charts.

Here is a comparison of 2003 and 2007 Line charts. As with XY charts, the Line charts show some improvement with 1023 MB over 513 MB, but the ratios between 2007 and 2003 are essentially unchanged.
With 1023 MB of RAM, the Excel 2007 Line charts take 15 to 22 times as long to redraw as the Excel 2003 Line charts.

Overall, charts in Excel 2007 are redrawn much more slowly than those in Excel 2003.

Update October 10, 2008

In a comment in a related post, Simon Murphy wondered how much of the chart redrawing discrepancy was due to slower recalculation in Excel 2007. I fired up the two VMs, and I ran tests measuring the time it takes to recalculate various numbers of cells. The results can be read in Excel 2007 Recalculates Slowly.

I populated by blank worksheet with “x” and “y” in cells A1 and B1, and =RAND() in A2 and B2. I extended row 2 down N rows to populate an XY chart with N points. The XY chart had default formatting with markers only, no lines, and the X and Y axis scales were set to automatic.

I automated recalculation in the worksheet using this command from the VB Editor’s Immediate Window:

debug.Print now, timer : for i=1 to 100 : activesheet.calculate : _
    next : debug.Print now, timer
 

which essentially recalculates the random numbers 100 times, recording the time (now outputs the date and time, timer outputs elapsed time in seconds) before and after the recalculations. Output of a typical run looked like this:

10/10/2008 9:00:55 AM        32455.06
10/10/2008 9:01:05 AM        32465.61
 

I calculated average chart redraw times by taking the difference between the two timer values, and dividing by 100. The times in Excel 2007 to redraw the chart for 100, 200, 500, and 1000 points is shown in this chart:

I remembered hearing that in the RTM version of Excel 2007, chart performance suffered if the axis scales were fixed, so I ran the same tests on a chart with fixed axes. It turns out that there’s very little difference.

Then I thought about the markers in the XY chart. They are made from the new Office shapes, which means they have built in the ability to contain all kinds of glittery effects, like gradients, shadows, bevels, glows, and the like. Perhaps If I made a line chart instead, with lines only and no markers, I would see a difference. (The line chart used only one column of random numbers.) In fact, there is a difference, and the line charts take substantially longer to plot.

I repeated the tests in my Excel 2003 VM. The line charts in Excel 2003 actually do take a shorter time to redraw than the XY charts. More striking is the different axis scale between the chart above and below this sentence.
The Excel 2007 charts take around an order of magnitude longer to redraw than the Excel 2003 charts.

The data I used in this analysis is available in ChtPerf2003v2007.csv. A pivot table I made from this data is shown below.

Here is a comparison of 2003 and 2007 XY charts.
The Excel 2007 XY charts take 8.5 to 10.4 times as long to redraw as the Excel 2003 XY charts.

Here is a comparison of 2003 and 2007 Line charts.
The Excel 2007 Line charts take 15 to 24 times as long to redraw as the Excel 2003 Line charts.

Overall, charts in Excel 2007 are redrawn much more slowly than those in Excel 2003.

Update October 10, 2008

In a comment below, Robert Kosara wondered whether using only 513 MB was strangling Excel 2007. I changed the settings on the two VMs so they each used 1023 MB, and I reran the tests. The results can be read in Excel 2007 Chart Performance – Revisited.

Update October 10, 2008

In a comment below, Simon Murphy wondered how much of the chart redrawing discrepancy was due to slower recalculation in Excel 2007. I fired up the two VMs, and I ran tests measuring the time it takes to recalculate various numbers of cells. The results can be read in Excel 2007 Recalculates Slowly.