-2.52% is the change from 991 to 966
Calculation steps:
[( 966 - 991 ) ÷ 991] x 100 = -2.52%
Formula
Percentage change = [(966 - 991) / 991] x 100
Subtract the new number by the original number
966 - 991 = -25
-25 ÷ 991 = -0.025227043390514632
-0.025227043390514632 x 100 = -2.52%