221% is the change from 100 to 321
Calculation steps:
[( 321 - 100 ) ÷ 100] x 100 = 221%
Formula
Percentage change = [(321 - 100) / 100] x 100
Subtract the new number by the original number
321 - 100 = 221
221 ÷ 100 = 2.21
2.21 x 100 = 221%
Example