-49.78% is the change from 687 to 345
Calculation steps:
[( 345 - 687 ) ÷ 687] x 100 = -49.78%
Formula
Percentage change = [(345 - 687) / 687] x 100
Subtract the new number by the original number
345 - 687 = -342
-342 ÷ 687 = -0.4978165938864629
-0.4978165938864629 x 100 = -49.78%