-3.3% is the change from 91 to 88
Calculation steps:
[( 88 - 91 ) ÷ 91] x 100 = -3.3%
Formula
Percentage change = [(88 - 91) / 91] x 100
Subtract the new number by the original number
88 - 91 = -3
-3 ÷ 91 = -0.03296703296703297
-0.03296703296703297 x 100 = -3.3%