2238.1% is the change from 21 to 491
Calculation steps:
[( 491 - 21 ) ÷ 21] x 100 = 2238.1%
Formula
Percentage change = [(491 - 21) / 21] x 100
Subtract the new number by the original number
491 - 21 = 470
470 ÷ 21 = 22.38095238095238
22.38095238095238 x 100 = 2238.1%