-82.8% is the change from 529 to 91
Calculation steps:
[( 91 - 529 ) ÷ 529] x 100 = -82.8%
Formula
Percentage change = [(91 - 529) / 529] x 100
Subtract the new number by the original number
91 - 529 = -438
-438 ÷ 529 = -0.8279773156899811
-0.8279773156899811 x 100 = -82.8%