-3.93% is the change from 178 to 171
Calculation steps:
[( 171 - 178 ) ÷ 178] x 100 = -3.93%
Formula
Percentage change = [(171 - 178) / 178] x 100
Subtract the new number by the original number
171 - 178 = -7
-7 ÷ 178 = -0.03932584269662921
-0.03932584269662921 x 100 = -3.93%