-90.33% is the change from 817 to 79
Calculation steps:
[( 79 - 817 ) ÷ 817] x 100 = -90.33%
Formula
Percentage change = [(79 - 817) / 817] x 100
Subtract the new number by the original number
79 - 817 = -738
-738 ÷ 817 = -0.9033047735618115
-0.9033047735618115 x 100 = -90.33%