-6.99% is the change from 915 to 851
Calculation steps:
[( 851 - 915 ) ÷ 915] x 100 = -6.99%
Formula
Percentage change = [(851 - 915) / 915] x 100
Subtract the new number by the original number
851 - 915 = -64
-64 ÷ 915 = -0.06994535519125683
-0.06994535519125683 x 100 = -6.99%