property Chart.HistogramBackColor as Color
Specifies the background color of the chart's histogram.

Color A Color expression that defines the histogram's background color. The last 7 bits in the high significant byte of the color indicates the identifier of the skin being used. Use the Add method to add new skins to the control. If you need to remove the skin appearance from a part of the control you need to reset the last 7 bits in the high significant byte of the color being applied to the background's part.
By default, the HistogramBackColor is changed when the BackColor property is changed. Use the HistogramVisible property to show or hide the histogram. Use the HistogramHeight property to specify at runtime the height of the histogram. Use the HistogramPattern and HistogramColor property to define the shape, the pattern, the color or the skinning object to be used in defining your histogram for specifies type of bar. The control allows to show workload and capacity by a histogram that automatically adapts to your current planning situation. The histogram may show the overloads and subloads for visible bars, or for selected bars. Over-loads and Sub-loads can be shown in several ways using curves, patterns or colors in the same histogram. They are updated interactively, so as user moves or resizes a bar, the histogram is updated automatically.