15.04% is the change from 266 to 306
Calculation steps:
[( 306 - 266 ) ÷ 266] x 100 = 15.04%
Formula
Percentage change = [(306 - 266) / 266] x 100
Subtract the new number by the original number
306 - 266 = 40
40 ÷ 266 = 0.15037593984962405
0.15037593984962405 x 100 = 15.04%