Calculate step Angle from Stepper Motor Counter

Hi,

I am looking for a formula to calculate the Stepper Motor Angle from the Stepper Motor Counter. The Stepper Motor has 1.8 Degree/200 Steps Resolution. As it rotates more than 200 Steps, I want the Angle to reset to 0 and start calculating again from 0 to 360 Degrees. As I am a beginner I am confused to use some sort of While or For Loop. Any suggestions?