-75.93% is the change from 511 to 123
Calculation steps:
[( 123 - 511 ) ÷ 511] x 100 = -75.93%
Formula
Percentage change = [(123 - 511) / 511] x 100
Subtract the new number by the original number
123 - 511 = -388
-388 ÷ 511 = -0.7592954990215264
-0.7592954990215264 x 100 = -75.93%