962.5% is the change from 80 to 850
Calculation steps:
[( 850 - 80 ) ÷ 80] x 100 = 962.5%
Formula
Percentage change = [(850 - 80) / 80] x 100
Subtract the new number by the original number
850 - 80 = 770
770 ÷ 80 = 9.625
9.625 x 100 = 962.5%
Example