-21.79% is the change from 78 to 61
Calculation steps:
[( 61 - 78 ) ÷ 78] x 100 = -21.79%
Formula
Percentage change = [(61 - 78) / 78] x 100
Subtract the new number by the original number
61 - 78 = -17
-17 ÷ 78 = -0.21794871794871795
-0.21794871794871795 x 100 = -21.79%