-50% is the change from 674 to 337
Calculation steps:
[( 337 - 674 ) ÷ 674] x 100 = -50%
Formula
Percentage change = [(337 - 674) / 674] x 100
Subtract the new number by the original number
337 - 674 = -337
-337 ÷ 674 = -0.5
-0.5 x 100 = -50%
Example