Dr. Nicolas Bissantz wrote in Do time series charts really compare time series? about time series being difficult to compare. The chart he discussed showed the cost of energy for three different heating methods. Says Nicolas, “The lines suggest that the price for heating oil has exploded, while electricity and natural gas have increased moderately.”
[...]

In the Calculating Easter post on John Walkenbach’s new Spreadsheet Page blog, John presented a bar chart showing the occurrences of the dates of Easter between 1900 and 2199. He sorted his dates in decreasing order of occurrence (below left). In Gradients, Fills, and Shadows, Oh My I proposed sorting in date order (below right).
[...]

There has been a lot of discussion here lately about XY and Line charts:

Line Charts vs. XY Charts
Line-XY Combination Charts
Category Axis Tricks for Line and Area Charts - 1
Category Axis Tricks for Line and Area Charts - 2
Order of Points in XY and Line Charts

Many of these posts have described differences between XY and [...]

There has been a lot of discussion here lately about XY and Line charts:

Line Charts vs. XY Charts
Line-XY Combination Charts
Category Axis Tricks for Line and Area Charts - 1
Category Axis Tricks for Line and Area Charts - 2

One interesting thing about a line chart with a date scale X axis is the order of the [...]

In Line Charts vs. XY Charts I described the difference between these two Excel chart types. There is no difference in the ways you can format the series, so perhaps the names of the chart types are confusing. The differences are in the ways their respective X axes treat the X data. I discussed the [...]

In More graphical propaganda, Andrew Gelman of the Statistical Modeling, Causal Inference, and Social Science blog shows some pie charts of recent Kenyan election results which he got from John Sides’ blog post, Election Fraud in Kenya in The Monkey Cage blog. The charts are awful; as Andrew notes, the colors change and the [...]

In Line-XY Combination Charts I showed how to make a combination Line-XY chart. It is probably important to discuss the differences between line charts and XY charts. The documentation is not clear, and the names of the chart types are not helpful; in fact, they lead to confusion.
The icons in the Chart Type dialog and [...]

When people think of an Excel combination chart, they usually think of a chart with lines and columns, or something similar that they found on the list of “Built-In Custom” chart types (I just love that oxymoron). However, line and XY series are types that combine to make decent charts. The line chart’s Date Scale [...]

In Category Axis Tricks for Line and Area Charts - 1, we saw how to use two line series to create a two-toned line chart. This is useful if we want to differentiate between actual values up to a certain date and predicted values thereafter, or if we want to distinguish values from different periods [...]

Let’s look at the behavior of line charts and the category axis. Here is some simple data I made up just for this exercise, and a typical line chart plotting the data.
 

Value

1
11

2
7

3
12

4
7

5
15

6
13

7
16

8
12

9
17

10
16

11
18

 
 
Okay, not too boring. Let’s see what happens if we split the data into two series, red and blue. The red series will include [...]