-15.84% is the change from 991 to 834
Calculation steps:
[( 834 - 991 ) ÷ 991] x 100 = -15.84%
Formula
Percentage change = [(834 - 991) / 991] x 100
Subtract the new number by the original number
834 - 991 = -157
-157 ÷ 991 = -0.1584258324924319
-0.1584258324924319 x 100 = -15.84%