-33.12% is the change from 770 to 515
Calculation steps:
[( 515 - 770 ) ÷ 770] x 100 = -33.12%
Formula
Percentage change = [(515 - 770) / 770] x 100
Subtract the new number by the original number
515 - 770 = -255
-255 ÷ 770 = -0.33116883116883117
-0.33116883116883117 x 100 = -33.12%