-21.23% is the change from 650 to 512
Calculation steps:
[( 512 - 650 ) ÷ 650] x 100 = -21.23%
Formula
Percentage change = [(512 - 650) / 650] x 100
Subtract the new number by the original number
512 - 650 = -138
-138 ÷ 650 = -0.2123076923076923
-0.2123076923076923 x 100 = -21.23%