-24.18% is the change from 819 to 621
Calculation steps:
[( 621 - 819 ) ÷ 819] x 100 = -24.18%
Formula
Percentage change = [(621 - 819) / 819] x 100
Subtract the new number by the original number
621 - 819 = -198
-198 ÷ 819 = -0.24175824175824176
-0.24175824175824176 x 100 = -24.18%