-33.21% is the change from 780 to 521
Calculation steps:
[( 521 - 780 ) ÷ 780] x 100 = -33.21%
Formula
Percentage change = [(521 - 780) / 780] x 100
Subtract the new number by the original number
521 - 780 = -259
-259 ÷ 780 = -0.33205128205128204
-0.33205128205128204 x 100 = -33.21%