-21.49% is the change from 991 to 778
Calculation steps:
[( 778 - 991 ) ÷ 991] x 100 = -21.49%
Formula
Percentage change = [(778 - 991) / 991] x 100
Subtract the new number by the original number
778 - 991 = -213
-213 ÷ 991 = -0.21493440968718466
-0.21493440968718466 x 100 = -21.49%