-98.42% is the change from 505 to 8
Calculation steps:
[( 8 - 505 ) ÷ 505] x 100 = -98.42%
Formula
Percentage change = [(8 - 505) / 505] x 100
Subtract the new number by the original number
8 - 505 = -497
-497 ÷ 505 = -0.9841584158415841
-0.9841584158415841 x 100 = -98.42%