-18.9% is the change from 1000 to 811
Calculation steps:
[( 811 - 1000 ) ÷ 1000] x 100 = -18.9%
Formula
Percentage change = [(811 - 1000) / 1000] x 100
Subtract the new number by the original number
811 - 1000 = -189
-189 ÷ 1000 = -0.189
-0.189 x 100 = -18.9%