-21.33% is the change from 511 to 402
Calculation steps:
[( 402 - 511 ) ÷ 511] x 100 = -21.33%
Formula
Percentage change = [(402 - 511) / 511] x 100
Subtract the new number by the original number
402 - 511 = -109
-109 ÷ 511 = -0.21330724070450097
-0.21330724070450097 x 100 = -21.33%