21400% is the change from 3 to 645
Calculation steps:
[( 645 - 3 ) ÷ 3] x 100 = 21400%
Formula
Percentage change = [(645 - 3) / 3] x 100
Subtract the new number by the original number
645 - 3 = 642
642 ÷ 3 = 214
214 x 100 = 21400%
Example