-97.22% is the change from 540 to 15
Calculation steps:
[( 15 - 540 ) ÷ 540] x 100 = -97.22%
Formula
Percentage change = [(15 - 540) / 540] x 100
Subtract the new number by the original number
15 - 540 = -525
-525 ÷ 540 = -0.9722222222222222
-0.9722222222222222 x 100 = -97.22%