-83.78% is the change from 561 to 91
Calculation steps:
[( 91 - 561 ) ÷ 561] x 100 = -83.78%
Formula
Percentage change = [(91 - 561) / 561] x 100
Subtract the new number by the original number
91 - 561 = -470
-470 ÷ 561 = -0.8377896613190731
-0.8377896613190731 x 100 = -83.78%