The inventory is valuated when the products are registered in stock so we can look up for the report in Inventory then Reports the Valuation, there we can find everything related to incoming and outgoing of stock and landed costs related to any stock movement so we can take that information and add it to a Spreadsheet.

After this we need to find the exchange rate that was being used in every stock movement, we can find that information in the currencies menu where we can see the exchange rate of everyday, we will need to create a menu that we can use to have it in the same Spreadsheet where we have the Valuation

 report.

The relation between the exchange rate and the stock movement is going to be the date so we can divide the cost in the base currency between the exchange rate to have the actual cost of that specific movement. Then we need to add formulas to the spreadsheet to have the accumulated cost of each movement by adding only the movements that have the same product related.

The date has different format between the currency exchange rate and the valorization of inventory so we need to create a format that we can match between the two of them, we have to create a column and use the formula: =LEFT(B2,5) this is how we are going to have a number format in the date in both dates.

To make the calculation of the cost of inventory in different currencies we need to add the following columns with the following formulas:

Exchange rate =VLOOKUP(A2,'Tipo de cambio'!$A$1:$E$38,5,0)

This is how we are going to be able to get the actual exchange rate used on de date of the stock movement.

Value of operation =I2*J2

With this formula we will know the cost in the foreign currency of the stock movement we are making.

Stock =SUMIF($D$1:$D$99,D2,$F$1:$F$99)

In this column we can track the actual amount of stock of a product after adding or taking out stock 

Avg Cost =IFERROR(IF(F2="","",SUMIF($C$1:$C$99,C2,$K$1:$K$99)/F2),"")

With the average cost we can see the average cost by unit of the movement because we will be dividing the quantity of product that we are moving by adding or subtracting between the cost of the operation.

Stock Value =SUMIF($D$1:$D$99,D2,$K$1:$K$99)

Here we will be able to know how much our whole stock is worth in the sum of all the stock movements according to the stock inputs and outputs.

Sum avg cost =SUMIF($D$1:$D$84,D2,$O$1:$O$84)

The last column we will have the added average cost of all the stock inputs and outputs by product.