-83.15% is the change from 819 to 138
Calculation steps:
[( 138 - 819 ) ÷ 819] x 100 = -83.15%
Formula
Percentage change = [(138 - 819) / 819] x 100
Subtract the new number by the original number
138 - 819 = -681
-681 ÷ 819 = -0.8315018315018315
-0.8315018315018315 x 100 = -83.15%