-83.95% is the change from 517 to 83
Calculation steps:
[( 83 - 517 ) ÷ 517] x 100 = -83.95%
Formula
Percentage change = [(83 - 517) / 517] x 100
Subtract the new number by the original number
83 - 517 = -434
-434 ÷ 517 = -0.839458413926499
-0.839458413926499 x 100 = -83.95%