In an accumulated chart, each y-value is added to the y-value of the following x-value. By choosing full accumulation you will get the accumulated sum of all previous values in the expression, by choosing accumulate x steps back you only get the x-latest values added to your value.
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By choosing between the settings in this group, you decide whether the values in the chart should be accumulated or not. In an accumulated chart, each y-value is added to the y-value of the following x-value. In an accumulated bar chart showing the sum of sales per year, e.g. the value of the year 1996 is added to that of the year 1997. If your chart contains several expressions, select the expression which values to be accumulated in the Expressions list. Accumulation is not available for pivot tables.
No Accumulation If this option is selected, the y-values of the selected chart expression will not be accumulated.
Full Accumulation If this option is selected, each y-value will accumulate all previous y-values of the expression. See above underAccumulation. Full accumulation does not work for multiple dimensions containing Null or 0 values.
Note:Full accumulation does not work if the chart trellis is enabled.
AccumulatenSteps Back By entering a number in the box, you set the number of y-values in the expression to be accumulated. See above underAccumulation.