-74.95% is the change from 511 to 128
Calculation steps:
[( 128 - 511 ) ÷ 511] x 100 = -74.95%
Formula
Percentage change = [(128 - 511) / 511] x 100
Subtract the new number by the original number
128 - 511 = -383
-383 ÷ 511 = -0.7495107632093934
-0.7495107632093934 x 100 = -74.95%