-35% is the change from 780 to 507
Calculation steps:
[( 507 - 780 ) ÷ 780] x 100 = -35%
Formula
Percentage change = [(507 - 780) / 780] x 100
Subtract the new number by the original number
507 - 780 = -273
-273 ÷ 780 = -0.35
-0.35 x 100 = -35%
Example