3028.57% is the change from 21 to 657
Calculation steps:
[( 657 - 21 ) ÷ 21] x 100 = 3028.57%
Formula
Percentage change = [(657 - 21) / 21] x 100
Subtract the new number by the original number
657 - 21 = 636
636 ÷ 21 = 30.285714285714285
30.285714285714285 x 100 = 3028.57%