Scaling tab

The Scaling tab is a tab of the Format Axis dialog.

The Scaling tab has different options for the Value and Category axes. In a Column chart, for example, the Value axis is the Y-axis. In a Bar chart, the Value axis is the X-axis.

Value axis

On the Scaling tab for the Value axis, you can specify these options:

  • The type of scaling
  • The values of the Major and Minor markers
  • The point at which the Value axis intersects with the Category axis
  • Whether the values on the axis are displayed in ascending or descending order
Type of scaling
Scaling can be Linear, Logarithmic or Time.
Linear scaling displays actual values on the Value axis. Logarithmic scaling displays logarithms of the values. Logarithmic scaling can be useful if the chart contains a wide range of values. For example, with Linear scaling, the Value axis of a column chart with the values 10, 20, 300 and 40000, would display 0 to 40000 in increments of 5000. In this case, columns for the lower values are too small to be displayed. But in this example, with Logarithmic scaling, the Value axis displays 10, 100, 10000 and 100000 and columns for all values can be displayed.
Milestone charts, for example, use Time scaling. The Value axis of a Milestone chart can display, for example, Months as the units of the major markers and 'week commencing' numbers as the units of the Minor markers, or Quarters as the Major units and Months as the Minor units.
Values
For each type of scaling, the values displayed on the axis are automatically assigned. But you can specify different values for these parameters:
  • Minimum: The lowest value to be displayed on the axis
  • Maximum: The highest value to be displayed on the axis
  • Major unit: The units which the Major markers represent
  • Minor unit: The units which the Minor markers represent
In a chart which, for example, includes values between 0 and 500, the Value axis might be marked in increments of 50. These increments are the Major markers. In this case, the Minor markers, the subdivisions, would typically represent increments of 10. To provide more detail, you might display the Minor markers in increments of 5 or even 1.
To change a value, clear its check box in the Auto column and specify the required value in the adjacent field.
You can also change the value at which the Category axis intersects with the Value axis. For example, in a Column chart containing only positive values, the Category axis is at right angles to the lowest value on the Value axis. But, to highlight the lower values, you might place the Category axis at right angles to a higher value. In this case, the lower values, although positive, would be displayed below the Category axis and the higher values above it.
You can display the Category axis at right angles to the lowest value on the Value axis, the highest value, or to a value which you specify.

If required, you can display the values of the axis in reverse order. That is, in, for example, a Column chart which displays positive values, the data series are displayed below the Category axis rather than above it.

If Time is the type of scaling, there are these options:

  • There are lists for the Major and Minor units from which you can select various units of time.
  • For both the Major and Minor units, you can specify the format in which they are displayed.
  • If the Value axis includes the current date, you can choose to display a line at the current date.
  • If the Major or Minor units are days, you can highlight Saturdays and Sundays. Select Color holidays.
  • You can specify the width occupied by individual days. Increasing the width has the effect of magnifying the chart. If necessary, you can specify a new start point for the chart. That is, you can exclude areas of the chart which do not contain data.
  • You can specify a gap between the axis and the chart data.

It is possible to use cell references in axis scaling. You can specify these values as reference:

  • A cell, for example =L15
  • A variable, for example ReportVariables.Scaling.text
  • A formula, for example =MAX(k14,L14,M14,N14)

Category axis

The Scaling tab has these options for the Category axis:
Category axis intersects at
As with the Value axis, you can specify at which point on the Category axis the Category ans Value axes intersect. You can display the Value axis at right angles to the lowest value on the Category axis, the highest value, or to a value which you specify.
Number of categories between tick mark labels
By default, each category on the Category axis is labeled. You can specify that only some categories are labeled. For example, if the categories are the years 2006 to 2010, specify that only 2006, 2008, and 2010 are displayed on the axis.
Number of categories between tick marks
By default, there is a mark on the axis to the left and to the right of each category. If required, you can specify that two or more categories are displayed between the marks.
Value axis intersects between categories
By default, the Value axis intersects the Category axis at a tick mark on the Category axis. If required, you can specify that the Value axis intersects half way between the tick marks which border a category. Select the Value axis intersects between categories check box.
Categories in reverse order
If required, you can specify that the categories are displayed in reverse order. That is, for example, from 2010 to 2006 instead of from 2006 to 2010.
Automatic
By default, all categories are displayed on the Category axis. If required, you can restrict which categories are displayed. There are two options. If, for example, there are six categories and you want to display only the first four, clear the Automatic check box and specify 4 in the Number of visible categories field.
But if, for example, there are six categories and you want to display only the last four, clear the Automatic check box and specify 4 in the Number of visible categories field. Specify 3 in the Start at category number field. Only categories 3, 4, 5 and 6 are displayed.
Note: By default, in View mode, the Category axis displays all the categories specified in the chart data. But the number displayed automatically in the Number of visible categories field depends on the sample data specified in the Chart Wizard. By default, three sample categories are displayed. You cannot increase the value in the Number of visible categories field beyond the number of sample categories specified in the Chart Wizard. But you can recreate the chart and specify the required number of categories in the Data Source step of the Chart Wizard.
For charts such as pie charts, which do not have axes, you can specify the number of categories on the Options tab of the Chart Options dialog.