-89.99% is the change from 899 to 90
Calculation steps:
[( 90 - 899 ) ÷ 899] x 100 = -89.99%
Formula
Percentage change = [(90 - 899) / 899] x 100
Subtract the new number by the original number
90 - 899 = -809
-809 ÷ 899 = -0.899888765294772
-0.899888765294772 x 100 = -89.99%