280.09% is the change from 221 to 840
Calculation steps:
[( 840 - 221 ) ÷ 221] x 100 = 280.09%
Formula
Percentage change = [(840 - 221) / 221] x 100
Subtract the new number by the original number
840 - 221 = 619
619 ÷ 221 = 2.8009049773755654
2.8009049773755654 x 100 = 280.09%