-83.37% is the change from 517 to 86
Calculation steps:
[( 86 - 517 ) ÷ 517] x 100 = -83.37%
Formula
Percentage change = [(86 - 517) / 517] x 100
Subtract the new number by the original number
86 - 517 = -431
-431 ÷ 517 = -0.8336557059961315
-0.8336557059961315 x 100 = -83.37%