-92.14% is the change from 509 to 40
Calculation steps:
[( 40 - 509 ) ÷ 509] x 100 = -92.14%
Formula
Percentage change = [(40 - 509) / 509] x 100
Subtract the new number by the original number
40 - 509 = -469
-469 ÷ 509 = -0.9214145383104125
-0.9214145383104125 x 100 = -92.14%