All your attributes are weighted differently for each class, but the respective formula outputs your Attack Power stat. Potency acts as a multiplier on that.

place an imaginary decimal behind the hundreds place digit and use it as a multiplier.

50 potency = 0.50x damage ( -50% power)

100 potency = 1.00x damage.

150 potency = 1.50x damage. ( +50% power)

260 potency = 2.60x damage (+160% power)


This is pretty much how it works.