-76.23% is the change from 509 to 121
Calculation steps:
[( 121 - 509 ) ÷ 509] x 100 = -76.23%
Formula
Percentage change = [(121 - 509) / 509] x 100
Subtract the new number by the original number
121 - 509 = -388
-388 ÷ 509 = -0.762278978388998
-0.762278978388998 x 100 = -76.23%