214.29% is the change from 210 to 660
Calculation steps:
[( 660 - 210 ) ÷ 210] x 100 = 214.29%
Formula
Percentage change = [(660 - 210) / 210] x 100
Subtract the new number by the original number
660 - 210 = 450
450 ÷ 210 = 2.142857142857143
2.142857142857143 x 100 = 214.29%