19.15% is the change from 820 to 977
Calculation steps:
[( 977 - 820 ) ÷ 820] x 100 = 19.15%
Formula
Percentage change = [(977 - 820) / 820] x 100
Subtract the new number by the original number
977 - 820 = 157
157 ÷ 820 = 0.19146341463414634
0.19146341463414634 x 100 = 19.15%