@Adrian_A, @Fardinkhan Omar  

Perhaps this is just a bad example, but I cannot think of any scenario where Advertising will be COGS.

COGS (Cost of Goods Sold) same as COS (Cost of Sales) are cost incurred directly attributable to sale. Advertising is considered Indirect expense, usually G&A (General and Administrative) or specifically,

Marketing or BD (Business Development) which are costs incurred to get new business so at the point 

when those cost are recorded, they would not be attributable to a sale that has not even occurred yet.