-19.03% is the change from 636 to 515
Calculation steps:
[( 515 - 636 ) ÷ 636] x 100 = -19.03%
Formula
Percentage change = [(515 - 636) / 636] x 100
Subtract the new number by the original number
515 - 636 = -121
-121 ÷ 636 = -0.19025157232704404
-0.19025157232704404 x 100 = -19.03%