Typically, you plot text or date-and-time data on the category (x) axis, which has regular segments that do not correspond to numerical values. If there are too many categories to fit within the finite limitations of the chart, you can use grouping. For example, group sales by quarter. By default, category values appear in the same order as they occur in the data source, unless sorted in another order by the query. You can sort the values in ascending or descending order using Edit Group and Sorting.

Typically, you plot numeric or date-and-time data on a value (y) axis. A value axis does not support plotting text data. A value axis positions data relative to the axis marks. The value of a data point determines where it appears on a value axis. Like data on the category axis, you can group and sort data on the value axis. Value series grouping defines sets of values.