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Controlling Chart Options
Chart type is just one of many options you can set for a chart. In the following sections I'll explain some of the elements you can display, hide, change, and reposition to change the way your data is presented.
Displaying and Positioning a Legend
The legend is the little box that sits to the side of the chart (or above or below it sometimes). It provides the key to what the different colors or patterns mean. Depending on the chart type and the labels in use, you may not find the legend useful.If not, you can turn it off by clicking the Legend button on the Standard toolbar. Turning off the legend makes more room for the chart, and it grows to fill the available space (see Figure 11-14).
Figure 11-14: Hide the chart's legend if it doesn't provide any needed information; hiding it gives more room to the chart.
| Caution | Hiding the legend is not a good idea if you have more than one series in your chart because the legend is instrumental in helping people decipher which series is which. However, if you have only one series, a legend is not necessary. It is also not necessary if you have some other indicators for the series, such as a data table or data labels that show the series. |
By default, the legend appears to the right of the chart, but you can place it somewhere else if you prefer. You can drag it anywhere you want it or change its position in the following way:
Choose Chart⇨Chart Options.
Click the Legend tab. If the Show Legend checkbox is not already marked, mark it.
Select the option representing the desired position, for example, Top, Bottom, Right, and so on(see Figure 11-15). Then click OK.
Figure 11-15: Position the legend in relation to the chart.
| Note | Don't worry if the text looks too big in the sample area or if some text is cut off, as shown in Figure 11-15. It will usually straighten itself out when you close the dialog box. And if it doesn't, you can always resize/reformat manually. |
The controls on the Placement tab in Figure 11-15 refer to the legend's position in relation to the chart, not to the legend text's position within the legend box.
Some people find the above method preferable to dragging the legend to move it because it changes the shape of the legend box as needed to accommodate its new position. Notice in Figure 11-15, for example, that the legend box runs horizontally when under the chart, whereas it's vertically oriented when at the side.You can also format the legend, just as you can format any other part of the chart. This is covered in detail later in the chapter, but if you want to experiment on your own, try dragging the selection handles for the legend's border to resize it and/or using the Font controls on the toolbar to change its font. You can also right-click it and choose Format Legend from the shortcut menu, or drag the legend where you want it.
Displaying Major and Minor Grid Lines
Grid lines are the marks on the wall behind the chart that help your eyes track across and up from the category and value axes. In most cases the default gridlines are appropriate, but you may want to turn on the non-default gridlines if the chart is not easily readable.If the audience needs to distinguish between two very similar values that are not adjacent on the chart, showing the minor gridlines can help the audience's eyes read the bars' positions better. For example, in Figure 11-16, the values of the bars are very similar, and it is difficult to tell exactly what value each bar represents. In Figure 11-17, with the minor gridlines turned on, it's easier to determine the value that each bar represents.
Figure 11-16: It is difficult to determine the exact values for these bars.
Figure 11-17: The minor gridlines make it obvious that the values for these bars are 21, 20, and 22.
To control the display of major and minor gridlines, choose Chart⇨Chart Options, and on the Gridlines tab, mark or clear checkboxes for the various types of gridlines (see Figure 11-18).
Figure 11-18: Turn on/off major and minor gridlines for each axis here.
| Tip | Making the major and minor gridlines different thicknesses or line styles will often improve the readability of a chart. To format gridlines, choose Chart⇨Chart Options and then right-click the appropriate gridline and choose Format Gridlines. You can set the line thickness (weight), color, style, and scale there. |
If you just want to toggle the major horizontal and vertical gridlines on and off, there's an easier way: the Category Axis Gridlines and Value Axis Gridlines buttons on the Standard toolbar.
Changing the Axis Scale
When you have a situation like the one shown in Figure 11-17, where you have very similar values for all the bars, it can be difficult to discern the differences between the values even with the major and minor gridlines turned on.It would be much easier to distinguish the values from one another if the scale were different. For example, in Figure 11-17, what if instead of the value (vertical) axis starting at 0 and ending at 25, it started at 19 and ended at 23? The differences between the values would be much more obvious then, as shown in Figure 11-19.
Figure 11-19: Change the value axis's scale to change the audience's perception of the differences between values.
You will probably never run into a case as dramatic as the difference between Figures 11-17 and 11-19 because Microsoft Graph has an Auto setting for the axis scale that's enabled by default. However, you may sometimes want to override the default scale for a special effect, such as to minimize or enhance the differences between data points. This is a good example of "making the data say what you want." If you wanted to make the point that the differences between the points are insignificant, you would use a larger scale. If you wanted to spotlight the importance of the differences, you would use a smaller scale.Axis scale is adjusted in the Format Axis dialog box for each axis (see Figure 11-20). To display it, point the mouse at the axis, right-click, and choose Format Axis. If there's no Format Axis command on the shortcut menu, you were not pointing at the right spot; try again.
Figure 11-20: Adjust the axis scale in the Format Axis dialog box.
| Tip | If you are having trouble selecting a part of the graph, use the drop-down list on the Standard toolbar to pinpoint it. |
The Auto checkbox for each item sets it so that Microsoft Graph chooses the setting. If you do not want the automatic value, deselect the Auto checkbox for it and enter a number manually in its text box. The following lists what each value represents:
Minimum is the starting number. The usual setting is 0, but in Figure 11-20 it starts at 19.
Maximum is the top number. It is 23 in Figure 11-20.
Major unit determines the axis labels (and also the major gridlines, if shown). On the chart in Figure 11-19, for example, notice that the numbers count by whole digits (19, 20, 21, 22, 23). That's because the Major Unit setting (as shown in Figure 11-20) is 1.
Minor unit determines the placement of minor gridlines, if shown.
Floor (XY Plane) or Category (X) Axis determines the place where the horizontal and vertical axes cross. This is normally the same as the Minimum value but could be different if you had a chart with values that descended below the horizontal axis line.
Logarithmic scale is rarely used by ordinary folks. It recalculates the Minimum, Maximum, Major Unit, and Minor Unit according to a power of 10 for the value axis based on the range of data. (If that explanation doesn't make any sense to you, you're not the target audience for this feature.)
Values in reverse order turns the scale backwards so the greater values are at the bottom or left.
Floor (XY plane) crosses at minimum value. This sets the value of the Floor (XY plane) crosses at setting to the smallest value represented on the axis.
| Note | Figures 11-19 and 11-20 are for a 3-D chart. If it's a 2-D chart, instead of Floor (XY Plane) in the preceding options, you will see Category X instead. And depending on the chart type, you might have a "crosses at maximum value" option, which would run the X axis across the top instead of the bottom. |
Changing the Axis Number Format
By default, the value axis shows plain numbers unless you have entered some type of special symbol such as dollar signs or percent signs in the data table along with your numbers.To make the numbers on the value axis appear as currency, dates, or in some other special numeric format, right-click the axis and choose Format Axis, displaying the Format Axis dialog box (same as in the preceding section). Then, click the Number tab and choose a number format there (see Figure 11-21). These number formats are the same as the ones available in Excel.
Figure 11-21: Adjust the number format in the Format Axis dialog box.
Displaying Data Labels
Data labels announce the value, percentage, series, and so on for a bar, slice, or other value marker. They aren't appropriate for every chart, because they tend to crowd one another on charts with tightly packed bars or other data representations. The best place to use them is on a pie chart, where there's a fairly large expanse of area for each slice. Category and percentage data labels are shown in Figure 11-22. Notice that this figure doesn't contain a legend. It doesn't need one because the data labels convey the legend information.
Figure 11-22: For some types of charts, data labels can help make the meaning clearer.
| Note | I have tinkered a bit with the formatting of the chart in Figure 11-22 to get it to look nicer. For example, I've made the data labels smaller in font size, and I've removed the black rectangular border around the plot area. If your chart is ugly, don't panic; you'll learn how to format it later in this chapter. |
Data labels are controlled from the Chart Options dialog box (Chart⇨Chart Options), on the Data Labels tab (see Figure 11-23). Mark the checkboxes there for each type of label you want. You can choose more than one, if desired:
Series name: The names of the data series from the legend. If you use this one, you don't need the legend.
Category name: The data from the category (X) axis.
Value: The actual value from the cell on the datasheet.
Percentage: What percentage of the whole each slice represents (not used on bar and column charts except for 100% stacked ones).
Bubble size: Applicable only for bubble charts. Indicates what each size represents.
Figure 11-23: Choose the type of data labels you want to appear on your chart.
You can also indicate a separator character, which will appear between each label type if you choose more than one type.
The Legend Key checkbox turns on/off the block of color beside the data label that corresponds to the legend color for it. This can be useful on a stacked chart where the items are difficult to see because they're so small.The Show Leader Lines checkbox enables/disables the use of callout lines that run between the labels and the corresponding slice or bar. On a simple chart, like in Figure 11-22, this is not necessary, but if you have a chart with many very thin pie slices it can help avoid confusion.
Adding Titles and Axis Labels
Most of the time, when you place a chart on a slide, that slide has its own title, so the chart itself does not need a separate title. However, if you have more on the slide than just the chart, it might be useful to have some text over the top of the chart to indicate why it's there. A title on the chart itself might also be useful if you plan to copy that chart into another application, such as Word.Besides an overall title for the chart, you can also add labels to each axis to describe the unit of measurement it shows (for example, Millions or Salespeople). Figure 11-24 shows a chart with axis labels for both vertical and horizontal axes and a chart title.
Figure 11-24: Axis labels can help explain a chart's message more clearly.
Titles and axis labels are set from the Chart Options dialog box (Chart⇨Chart Options), on the Titles tab (see Figure 11-25). Simply enter the text you want to appear in those locations and click OK. Each label appears in its own text box. Then format the text as you would any other text box (font, size, color, placement, and so on).
Figure 11-25: Enter the titles and labels you want to use.
| Caution | When you add titles, they take away from the available space for the plot area in the chart frame. The chart in the plot area appears smaller after you add titles because it has to shrink so that there will be room for the titles and labels to fit in the chart frame. One way to minimize the space taken up by these labels is to set them in a smaller font or, in the case of the vertical axis label, to rotate the text so it runs parallel to the axis. See Formatting Titles and Labels later in this chapter for more details. |
Adding a Data Table
Sometimes the chart tells the full story that you want to tell, but other times the audience may benefit from seeing the actual numbers on which the chart is built. In those cases it's a good idea to include the data table with the chart. (The data table contains the same information that appears on the datasheet.) To display the data table with a chart, click the Data Table button on the Standard toolbar (see Figure 11-26). If you don't see the Data Table button, make sure you have double-clicked the chart to activate it.
Figure 11-26: Use a data table to show the audience the numbers that formed the chart.
| Caution | Sometimes Microsoft Graph doesn't do a very good job of appropriately sizing the fonts in the data table. If the text is too big, you can adjust it. Right-click the data table, choose Format Data Table, and then on the Font tab, choose a different font size. You can also control the gridline appearance for the data table from this same dialog box. |
