-99.75% is the change from 815 to 2
Calculation steps:
[( 2 - 815 ) ÷ 815] x 100 = -99.75%
Formula
Percentage change = [(2 - 815) / 815] x 100
Subtract the new number by the original number
2 - 815 = -813
-813 ÷ 815 = -0.9975460122699387
-0.9975460122699387 x 100 = -99.75%