-13.64% is the change from 198 to 171
Calculation steps:
[( 171 - 198 ) ÷ 198] x 100 = -13.64%
Formula
Percentage change = [(171 - 198) / 198] x 100
Subtract the new number by the original number
171 - 198 = -27
-27 ÷ 198 = -0.13636363636363635
-0.13636363636363635 x 100 = -13.64%