309.52% is the change from 21 to 86
Calculation steps:
[( 86 - 21 ) ÷ 21] x 100 = 309.52%
Formula
Percentage change = [(86 - 21) / 21] x 100
Subtract the new number by the original number
86 - 21 = 65
65 ÷ 21 = 3.0952380952380953
3.0952380952380953 x 100 = 309.52%