50.29% is the change from 171 to 257
Calculation steps:
[( 257 - 171 ) ÷ 171] x 100 = 50.29%
Formula
Percentage change = [(257 - 171) / 171] x 100
Subtract the new number by the original number
257 - 171 = 86
86 ÷ 171 = 0.5029239766081871
0.5029239766081871 x 100 = 50.29%