-22% is the change from 100 to 78
Calculation steps:
[( 78 - 100 ) ÷ 100] x 100 = -22%
Formula
Percentage change = [(78 - 100) / 100] x 100
Subtract the new number by the original number
78 - 100 = -22
-22 ÷ 100 = -0.22
-0.22 x 100 = -22%
Example