-87.08% is the change from 991 to 128
Calculation steps:
[( 128 - 991 ) ÷ 991] x 100 = -87.08%
Formula
Percentage change = [(128 - 991) / 991] x 100
Subtract the new number by the original number
128 - 991 = -863
-863 ÷ 991 = -0.8708375378405651
-0.8708375378405651 x 100 = -87.08%