-87.11% is the change from 512 to 66
Calculation steps:
[( 66 - 512 ) ÷ 512] x 100 = -87.11%
Formula
Percentage change = [(66 - 512) / 512] x 100
Subtract the new number by the original number
66 - 512 = -446
-446 ÷ 512 = -0.87109375
-0.87109375 x 100 = -87.11%