Microsoft Office Tutorials and References
In Depth Information
You’ll want to know about the Vertical Axis Maximum and Minimum Value Options . The default
Automatic for each Sparkline option means that Excel will decide which numeric intervals will appear on
each Sparkline’s Vertical Axis, after looking at the data. Thus two Sparkline line charts—to return to two
previous examples, one charting a player’s batting averages across his career, the other a series of weight
measurements—will use different intervals on their axes, because the magnitudes are very different. If
you select the same for both Sparklines here, the batting averages and weights will use the same interval
scale—bringing about highly distorted outcomes (Figure 5-81):
Figure 5–81. Heavy hitters: Batting averages charted next to player weights
When they say a player can’t hit his weight, they mean it. The way to make these data readable in
their own terms is to remain with the default Automatic for Each Sparkline , and to set the Custom
Value… option to 0. If you don’t carry out that latter step, the lowest value in each data series is treated
as a de factto zero value, with the other values keyed to it.
As implied above, Custom Value enables you to enter the lowest and highest values of any number
that you’ll allow to appear in a Sparkline. If I enter a lowest allowable value of 1 for the batting average
Sparkline, I’ll see nothing in it—because all the batting averages are fractions, and thus all less than 1.
Charting Excel data calls for a two-front approach to the data—understanding how to portray the data in
a lucid and appealing format, and understanding at the same time what you need to do in order to bring
that end about. As we’ve seen, charting options are numerous and variable, depending on the chart
you’ve selected. As always, a bit of practice with real-world charting questions is key. Next up is a closer
look at the data contributing to charts and other Excel capabilities—the world of Excel databases.
Now go out there and cell those charts.