-78.71% is the change from 991 to 211
Calculation steps:
[( 211 - 991 ) ÷ 991] x 100 = -78.71%
Formula
Percentage change = [(211 - 991) / 991] x 100
Subtract the new number by the original number
211 - 991 = -780
-780 ÷ 991 = -0.7870837537840565
-0.7870837537840565 x 100 = -78.71%