-80.04% is the change from 501 to 100
Calculation steps:
[( 100 - 501 ) ÷ 501] x 100 = -80.04%
Formula
Percentage change = [(100 - 501) / 501] x 100
Subtract the new number by the original number
100 - 501 = -401
-401 ÷ 501 = -0.8003992015968064
-0.8003992015968064 x 100 = -80.04%