Applying range names to previously created formulas

[MJexcel0001]

I have a small table with named ranges: item, price, and quantity. The final column is COGS and is a formula without reference to the previously named ranges, only the cell references (for example, B2*C2). When applying the formula names through formulas, apply names (price and quantity) to COGS, the result is a spill error, #SPILL! for all rows of COGS (see below). Is this means of applying range names post-formula not viable? 

[#2]

@MJexcel0001 The formula =price*quantity (referring to the named ranges you've defined) will produce an array of results for every item in the table and return those results in a dynamic spilled array. You can enter this formula in, for example, cell F2 to see how the results spill in a range on the worksheet. Dynamic array formulas like these cannot be used within a structured Excel table, nor are they necessary, because structured tables already have built-in names for each column that can be referenced to create a calculated column. The implicit intersection operator "@" is used to reference "This Row" of the table, so you need only use =[@price]*[@quantity] to create the calculated column.

[#3]

@djclements Thank you for the quick and helpful response. It works and I appreciate it.