-80.1% is the change from 1000 to 199
Calculation steps:
[( 199 - 1000 ) ÷ 1000] x 100 = -80.1%
Formula
Percentage change = [(199 - 1000) / 1000] x 100
Subtract the new number by the original number
199 - 1000 = -801
-801 ÷ 1000 = -0.801
-0.801 x 100 = -80.1%