85.71% is the change from 210 to 390
Calculation steps:
[( 390 - 210 ) ÷ 210] x 100 = 85.71%
Formula
Percentage change = [(390 - 210) / 210] x 100
Subtract the new number by the original number
390 - 210 = 180
180 ÷ 210 = 0.8571428571428571
0.8571428571428571 x 100 = 85.71%