290% is the change from 20 to 78
Calculation steps:
[( 78 - 20 ) ÷ 20] x 100 = 290%
Formula
Percentage change = [(78 - 20) / 20] x 100
Subtract the new number by the original number
78 - 20 = 58
58 ÷ 20 = 2.9
2.9 x 100 = 290%
Example