285.71% is the change from 21 to 81
Calculation steps:
[( 81 - 21 ) ÷ 21] x 100 = 285.71%
Formula
Percentage change = [(81 - 21) / 21] x 100
Subtract the new number by the original number
81 - 21 = 60
60 ÷ 21 = 2.857142857142857
2.857142857142857 x 100 = 285.71%