19.53% is the change from 215 to 257
Calculation steps:
[( 257 - 215 ) ÷ 215] x 100 = 19.53%
Formula
Percentage change = [(257 - 215) / 215] x 100
Subtract the new number by the original number
257 - 215 = 42
42 ÷ 215 = 0.19534883720930232
0.19534883720930232 x 100 = 19.53%