-14.73% is the change from 645 to 550
Calculation steps:
[( 550 - 645 ) ÷ 645] x 100 = -14.73%
Formula
Percentage change = [(550 - 645) / 645] x 100
Subtract the new number by the original number
550 - 645 = -95
-95 ÷ 645 = -0.14728682170542637
-0.14728682170542637 x 100 = -14.73%