The Polar chart type is a circular graph on which data points are displayed using the angle, and the distance from the center point. The X axis is located on the boundaries of the circle and the Y axis connects the center of the circle with the X axis.
By default, the angle scale ranges from 0 to 360 degrees. However, the X Axis Minimum and Maximum properties may be used to specify a different angular scale. The minimum angle value starts at the top (12 o'clock position) of the chart but can be changed to another angle using the Crossing property. For example, setting the Crossing property to 90 moves the "zero" value to the 3 o'clock position.