171.88% is the change from 320 to 870
Calculation steps:
[( 870 - 320 ) ÷ 320] x 100 = 171.88%
Formula
Percentage change = [(870 - 320) / 320] x 100
Subtract the new number by the original number
870 - 320 = 550
550 ÷ 320 = 1.71875
1.71875 x 100 = 171.88%