Thank you for your reply!
I tried adding that function to my report, but I kept getting SELECT errors. Here is my report below:
I just want the total sum of the assets, but I cannot integrate it into my report 
 
 Select Top 1000000 tsysOS.Image As icon,
  tblAssets.AssetID,
  tblAssets.AssetName As Asset,
  tblAssets.Domain,
  tblAssetCustom.Manufacturer As Make,
  tblAssetCustom.Model,
  tsysOS.OSname As OS,
  tblAssets.Username As [User],
  tblAssets.Firstseen As [First Seen],
  tblAssets.Lastseen As [Last Seen],
  tblAssetCustom.PurchaseDate As [PC Purchase Date],
  tblAssetCustom.Warrantydate As [Warranty End Date],
  DateAdd(year, 5, tblAssetCustom.PurchaseDate) As [Replacement Date],
  Max(tblQuickFixEngineering.Lastchanged) As [Last Patch Detected]
From tblAssets
  Inner Join tblQuickFixEngineering On tblAssets.AssetID =
    tblQuickFixEngineering.AssetID
  Inner Join tblAssetCustom On tblAssets.AssetID = tblAssetCustom.AssetID
  Inner Join tsysOS On tsysOS.OScode = tblAssets.OScode
  Inner Join tblQuickFixEngineeringUni On tblQuickFixEngineeringUni.QFEID =
    tblQuickFixEngineering.QFEID
Group By tsysOS.Image,
  tblAssets.AssetID,
  tblAssets.AssetName,
  tblAssets.Domain,
  tblAssetCustom.Manufacturer,
  tblAssetCustom.Model,
  tsysOS.OSname,
  tblAssets.Username,
  tblAssets.Firstseen,
  tblAssets.Lastseen,
  tblAssetCustom.PurchaseDate,
  tblAssetCustom.Warrantydate
Order By Asset