Larry,
  22 teeth per inch on the belt would be .0454545 inch per tooth.
A 9mm OD pulley x pi would give a circumference of  1.113 / .0454545 = 24.49 so I will assume 24 teeth on the pulley.
24 x .0454545 = 1.090909 inches of travel per 1 rev. of the motor.
1.090909 / 200 = .00545454 inches per pulse (200 ppr, 1.8 degree stepper)
1 / .00545454 = 183.33 steps per inch.... multiplied by any micro stepping set at the driver.

Can you check in Motor Tuning and see what your steps per are set at now ?
Just curious....hoping my math is close. My cyferin' ain't the best.
Russ