21.51% is the change from 172 to 209
Calculation steps:
[( 209 - 172 ) ÷ 172] x 100 = 21.51%
Formula
Percentage change = [(209 - 172) / 172] x 100
Subtract the new number by the original number
209 - 172 = 37
37 ÷ 172 = 0.21511627906976744
0.21511627906976744 x 100 = 21.51%