-18.03% is the change from 821 to 673
Calculation steps:
[( 673 - 821 ) ÷ 821] x 100 = -18.03%
Formula
Percentage change = [(673 - 821) / 821] x 100
Subtract the new number by the original number
673 - 821 = -148
-148 ÷ 821 = -0.18026796589524968
-0.18026796589524968 x 100 = -18.03%