-1.17% is the change from 171 to 169
Calculation steps:
[( 169 - 171 ) ÷ 171] x 100 = -1.17%
Formula
Percentage change = [(169 - 171) / 171] x 100
Subtract the new number by the original number
169 - 171 = -2
-2 ÷ 171 = -0.011695906432748537
-0.011695906432748537 x 100 = -1.17%