-37.61% is the change from 819 to 511
Calculation steps:
[( 511 - 819 ) ÷ 819] x 100 = -37.61%
Formula
Percentage change = [(511 - 819) / 819] x 100
Subtract the new number by the original number
511 - 819 = -308
-308 ÷ 819 = -0.37606837606837606
-0.37606837606837606 x 100 = -37.61%