-3.21% is the change from 312 to 302
Calculation steps:
[( 302 - 312 ) ÷ 312] x 100 = -3.21%
Formula
Percentage change = [(302 - 312) / 312] x 100
Subtract the new number by the original number
302 - 312 = -10
-10 ÷ 312 = -0.03205128205128205
-0.03205128205128205 x 100 = -3.21%
Example