BCGSuite for MFC
double BCGPChartDataLabelOptions::m_dblMaxWidthToHeightRatio

Specifies the width to height ratio when data label's text is wrapped.

Specify this parameter to control maximal width of data label's rectangle when the word wrapping is enabled. The default value is 6, which means that the text will be wrapped when its width exceeds its height by 6 times.

The new bounding rectangle will be calculated as current text size (before wrap) divided by desired line count, which is specified by m_dblLineCount property.