4850% is the change from 20 to 990
Calculation steps:
[( 990 - 20 ) ÷ 20] x 100 = 4850%
Formula
Percentage change = [(990 - 20) / 20] x 100
Subtract the new number by the original number
990 - 20 = 970
970 ÷ 20 = 48.5
48.5 x 100 = 4850%
Example