-16.63% is the change from 505 to 421
Calculation steps:
[( 421 - 505 ) ÷ 505] x 100 = -16.63%
Formula
Percentage change = [(421 - 505) / 505] x 100
Subtract the new number by the original number
421 - 505 = -84
-84 ÷ 505 = -0.16633663366336635
-0.16633663366336635 x 100 = -16.63%
Example