19.4% is the change from 830 to 991
Calculation steps:
[( 991 - 830 ) ÷ 830] x 100 = 19.4%
Formula
Percentage change = [(991 - 830) / 830] x 100
Subtract the new number by the original number
991 - 830 = 161
161 ÷ 830 = 0.19397590361445782
0.19397590361445782 x 100 = 19.4%