-96.11% is the change from 540 to 21
Calculation steps:
[( 21 - 540 ) ÷ 540] x 100 = -96.11%
Formula
Percentage change = [(21 - 540) / 540] x 100
Subtract the new number by the original number
21 - 540 = -519
-519 ÷ 540 = -0.9611111111111111
-0.9611111111111111 x 100 = -96.11%