-18.86% is the change from 827 to 671
Calculation steps:
[( 671 - 827 ) ÷ 827] x 100 = -18.86%
Formula
Percentage change = [(671 - 827) / 827] x 100
Subtract the new number by the original number
671 - 827 = -156
-156 ÷ 827 = -0.18863361547763
-0.18863361547763 x 100 = -18.86%