263.53% is the change from 85 to 309
Calculation steps:
[( 309 - 85 ) ÷ 85] x 100 = 263.53%
Formula
Percentage change = [(309 - 85) / 85] x 100
Subtract the new number by the original number
309 - 85 = 224
224 ÷ 85 = 2.635294117647059
2.635294117647059 x 100 = 263.53%