The chart's ContourLevels determine how many contour lines and zoning colors are used in the chart, and the Z-values that mark each level. The number of levels or the distribution table itself can be customized.

To generate contours and zones, the chart analyzes the data and based on the number of levels specified, creates the following:

• A linear distribution table that contains the Z-value that marks each level.
• An assignment of ContourStyles from the chart's one hundred built-in styles. The chart determines which styles to use by evenly distributing its one hundred styles through the number of levels.