23.53% is the change from 170 to 210
Calculation steps:
[( 210 - 170 ) ÷ 170] x 100 = 23.53%
Formula
Percentage change = [(210 - 170) / 170] x 100
Subtract the new number by the original number
210 - 170 = 40
40 ÷ 170 = 0.23529411764705882
0.23529411764705882 x 100 = 23.53%