-25% is the change from 828 to 621
Calculation steps:
[( 621 - 828 ) ÷ 828] x 100 = -25%
Formula
Percentage change = [(621 - 828) / 828] x 100
Subtract the new number by the original number
621 - 828 = -207
-207 ÷ 828 = -0.25
-0.25 x 100 = -25%
Example