-9.88% is the change from 172 to 155
Calculation steps:
[( 155 - 172 ) ÷ 172] x 100 = -9.88%
Formula
Percentage change = [(155 - 172) / 172] x 100
Subtract the new number by the original number
155 - 172 = -17
-17 ÷ 172 = -0.09883720930232558
-0.09883720930232558 x 100 = -9.88%