-33.37% is the change from 815 to 543
Calculation steps:
[( 543 - 815 ) ÷ 815] x 100 = -33.37%
Formula
Percentage change = [(543 - 815) / 815] x 100
Subtract the new number by the original number
543 - 815 = -272
-272 ÷ 815 = -0.3337423312883436
-0.3337423312883436 x 100 = -33.37%