I have run a SQL query in SQL Server Management Studio 2005 and when my results come through my `Total_Cost` column is not formatted as I want.

I have tried adding in a `Declare @TOTAL_COST decimal(12,2)` clause but cannot seem to get this to work so have taken it out again.

My query is:-

```
SELECT     
   vwREP_GP_ContractProjectPurchaseCostCatID.PACOSTCATID AS COST_CAT_CODE, 
   vwREP_GP_ContractProjectPurchaseCostCatID.PACOSTCATNME AS COST_CAT_NAME, 
   vwREP_GP_ContractProjectPurchaseRpt.COST, 
   vwREP_GP_ContractProjectPurchaseRpt.ITEMDESC AS ITEM, 
   vwREP_GP_ContractProjectPurchaseRpt.CREDITOR, 
   vwREP_GP_ContractProjectPurchaseRpt.DOC_NUM AS DOCUMENT_NUMBER, 
   vwREP_GP_ContractProjectPurchaseRpt.DESCRIPTION, 
   vwREP_GP_ContractProjectPurchaseRpt.DOC_DATE AS DATE,  
   vwREP_GP_ContractProjectPurchaseRpt.PROJECT AS JOB_CODE_STAGE, 
   vwREP_GP_ContractProjectPurchaseRpt.COMPOUNDNAME AS CATEGORY_DESCRIPTION
FROM         
   vwREP_GP_ContractProjectPurchaseCostCatID 
INNER JOIN
   vwREP_GP_ContractProjectPurchaseRpt ON vwREP_GP_ContractProjectPurchaseCostCatID.PACOSTCATID = vwREP_GP_ContractProjectPurchaseRpt.PACOSTCATID

SELECT  
   CATEGORY_DESCRIPTION, SUM(COST) AS TOTAL_COST 
FROM    
   (SELECT 
        COMPOUNDNAME AS CATEGORY_DESCRIPTION, COST 
    FROM   
        vwREP_GP_ContractProjectPurchaseRpt 
   ) A
GROUP BY 
    CATEGORY_DESCRIPTION 

```

This gives me the results I am looking for but the `Total_Cost` produces numbers in a 5 decimal format. 

For example:

```
156713.55000

```

What is the best way to get the result to read something along the lines of - 

```
156713.55

```

Thanks in advance