-0.66% is the change from 915 to 909
Calculation steps:
[( 909 - 915 ) ÷ 915] x 100 = -0.66%
Formula
Percentage change = [(909 - 915) / 915] x 100
Subtract the new number by the original number
909 - 915 = -6
-6 ÷ 915 = -0.006557377049180328
-0.006557377049180328 x 100 = -0.66%