Microsoft Office Tutorials and References

In Depth Information

**Scatter Charts and Line Charts**

FIGURE 6.13
Formatting a Series

Scatter Charts and Line Charts

Scatter charts and line charts are very similar, especially when you create a scatter

chart with lines connecting the points

these charts look and feel like a line chart.

However, there is a fundamental difference between them.

Scatter charts
are used to display and compare numeric values, such as statistical

data. These charts are helpful to show the relationships among the numeric values of

several data series. You can plot two groups of numbers as one series of XY

coordinates.

Line charts
are used to display continuous data over time against a common

scale. They are good for showing trends in data at equal intervals. In line charts

categorical data is distributed evenly along the horizontal X-axis, and values are

distributed evenly along the Y-axis.

Choose between the two options using this rule: use line charts if the data has

nonnumeric X values

—

and use scatter charts for numeric X values. The following

example will clarify the fundamental difference.

On the sheet named Line vs. Scatter of the Excel Chapter 6 file, I selected sales

data from 1990 to 2008. I created a line chart and a scatter chart for the same data.

The line chart in Figure 6.14 distorts the data since the years, on the X-axis, are not

displayed proportionally. Look at the X-axis values: The years

—

labels are spaced

evenly, even though the data (the difference between the periods) is unequal. They are

not spaced proportionately.

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