2100% is the change from 3 to 66
Calculation steps:
[( 66 - 3 ) ÷ 3] x 100 = 2100%
Formula
Percentage change = [(66 - 3) / 3] x 100
Subtract the new number by the original number
66 - 3 = 63
63 ÷ 3 = 21
21 x 100 = 2100%
Example