4250% is the change from 20 to 870
Calculation steps:
[( 870 - 20 ) ÷ 20] x 100 = 4250%
Formula
Percentage change = [(870 - 20) / 20] x 100
Subtract the new number by the original number
870 - 20 = 850
850 ÷ 20 = 42.5
42.5 x 100 = 4250%
Example