This property is only applicable to pie and doughnut charts.
The valid range for this property is 0 through 360, inclusive. Fractional angles are not supported; nor are negative angles.
By default, the first slice begins at the "12 o'clock" position of the pie chart, i.e., the top center point of the encompassing circle.
Use this property to offset the origin of the first slice; for example, a value of 30 positions the first slice at the 1 o'clock position, 60 at the 2 o'clock position, 90 for 3 o'clock, etc.
Larger values move along the circumference of the emcompassing circle in a clockwise direction, with a value of 0 or 360 both coinciding with the 12 o'clock position.
Target Platforms: Android 4.4+, iOS 8+
Development Environments: Visual Studio 2015+, Visual Studio for Mac Preview, Xamarin for Visual Studio 4.2+