-64.1% is the change from 780 to 280
Calculation steps:
[( 280 - 780 ) ÷ 780] x 100 = -64.1%
Formula
Percentage change = [(280 - 780) / 780] x 100
Subtract the new number by the original number
280 - 780 = -500
-500 ÷ 780 = -0.6410256410256411
-0.6410256410256411 x 100 = -64.1%