By default, the HistogramCumulativeShowLegend property is 0 which means that the column with the index 0 is used to display the legend for the items being included in the histogram. The HistogramCumulativeShowLegend property has effect only if the HistogramType property includes the exHistCumulative flag. The HistogramCumulativeColors property specifies the number of colors being used to display the cumulative histogram for a bar. The HistogramCumulativeColor property specifies a color being used when showing cumulative histogram.  Use the HistogramCumulativeOriginalColorBars property to specify whether the bars that generated the cumulative histogram change their original colors. Use the Item property to access a column in the columns collection.