-32.8% is the change from 991 to 666
Calculation steps:
[( 666 - 991 ) ÷ 991] x 100 = -32.8%
Formula
Percentage change = [(666 - 991) / 991] x 100
Subtract the new number by the original number
666 - 991 = -325
-325 ÷ 991 = -0.32795156407669024
-0.32795156407669024 x 100 = -32.8%