-18.45% is the change from 515 to 420
Calculation steps:
[( 420 - 515 ) ÷ 515] x 100 = -18.45%
Formula
Percentage change = [(420 - 515) / 515] x 100
Subtract the new number by the original number
420 - 515 = -95
-95 ÷ 515 = -0.18446601941747573
-0.18446601941747573 x 100 = -18.45%