2.16% is the change from 970 to 991
Calculation steps:
[( 991 - 970 ) ÷ 970] x 100 = 2.16%
Formula
Percentage change = [(991 - 970) / 970] x 100
Subtract the new number by the original number
991 - 970 = 21
21 ÷ 970 = 0.021649484536082474
0.021649484536082474 x 100 = 2.16%