-90% is the change from 290 to 29
Calculation steps:
[( 29 - 290 ) ÷ 290] x 100 = -90%
Formula
Percentage change = [(29 - 290) / 290] x 100
Subtract the new number by the original number
29 - 290 = -261
-261 ÷ 290 = -0.9
-0.9 x 100 = -90%
Example