-99.7% is the change from 673 to 2
Calculation steps:
[( 2 - 673 ) ÷ 673] x 100 = -99.7%
Formula
Percentage change = [(2 - 673) / 673] x 100
Subtract the new number by the original number
2 - 673 = -671
-671 ÷ 673 = -0.9970282317979198
-0.9970282317979198 x 100 = -99.7%