3852.38% is the change from 21 to 830
Calculation steps:
[( 830 - 21 ) ÷ 21] x 100 = 3852.38%
Formula
Percentage change = [(830 - 21) / 21] x 100
Subtract the new number by the original number
830 - 21 = 809
809 ÷ 21 = 38.523809523809526
38.523809523809526 x 100 = 3852.38%