-17.59% is the change from 813 to 670
Calculation steps:
[( 670 - 813 ) ÷ 813] x 100 = -17.59%
Formula
Percentage change = [(670 - 813) / 813] x 100
Subtract the new number by the original number
670 - 813 = -143
-143 ÷ 813 = -0.17589175891758918
-0.17589175891758918 x 100 = -17.59%