-19.05% is the change from 819 to 663
Calculation steps:
[( 663 - 819 ) ÷ 819] x 100 = -19.05%
Formula
Percentage change = [(663 - 819) / 819] x 100
Subtract the new number by the original number
663 - 819 = -156
-156 ÷ 819 = -0.19047619047619047
-0.19047619047619047 x 100 = -19.05%