-22.48% is the change from 645 to 500
Calculation steps:
[( 500 - 645 ) ÷ 645] x 100 = -22.48%
Formula
Percentage change = [(500 - 645) / 645] x 100
Subtract the new number by the original number
500 - 645 = -145
-145 ÷ 645 = -0.2248062015503876
-0.2248062015503876 x 100 = -22.48%