-35.9% is the change from 780 to 500
Calculation steps:
[( 500 - 780 ) ÷ 780] x 100 = -35.9%
Formula
Percentage change = [(500 - 780) / 780] x 100
Subtract the new number by the original number
500 - 780 = -280
-280 ÷ 780 = -0.358974358974359
-0.358974358974359 x 100 = -35.9%