-84.5% is the change from 1000 to 155
Calculation steps:
[( 155 - 1000 ) ÷ 1000] x 100 = -84.5%
Formula
Percentage change = [(155 - 1000) / 1000] x 100
Subtract the new number by the original number
155 - 1000 = -845
-845 ÷ 1000 = -0.845
-0.845 x 100 = -84.5%