-2.5% is the change from 360 to 351
Calculation steps:
[( 351 - 360 ) ÷ 360] x 100 = -2.5%
Formula
Percentage change = [(351 - 360) / 360] x 100
Subtract the new number by the original number
351 - 360 = -9
-9 ÷ 360 = -0.025
-0.025 x 100 = -2.5%
Example