Custom property with 10 steps

Hi,

I created a custom property to rotate a cube on z-axis.
The property goes from 0 to 1 the cube should rotate from 0 to 90 degrees.
But if I change the value by clicking the small left and right arrow of the property value it increases always in decimal way. This means it goes e.g. from 0.010, 0.020, up to 1.000, this are a lot of clicks I have to do to get from 0 to 1.
If I use the mouse-drag to increase I have to move the mouse over the half of the table to get the value from 0 to 1.
Is it possible to set a step size? I want to get from 0 to 1 in only 10 steps.

Thanks!

Probably should ask in the Python section.