21.59% is the change from 820 to 997
Calculation steps:
[( 997 - 820 ) ÷ 820] x 100 = 21.59%
Formula
Percentage change = [(997 - 820) / 820] x 100
Subtract the new number by the original number
997 - 820 = 177
177 ÷ 820 = 0.21585365853658536
0.21585365853658536 x 100 = 21.59%