87.13% is the change from 171 to 320
Calculation steps:
[( 320 - 171 ) ÷ 171] x 100 = 87.13%
Formula
Percentage change = [(320 - 171) / 171] x 100
Subtract the new number by the original number
320 - 171 = 149
149 ÷ 171 = 0.8713450292397661
0.8713450292397661 x 100 = 87.13%