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Using this tab, you can enter the beginning balances of revenues recognized for contracts for which work is still in progress.
The Opening Balances Entering document. The Contract Assets tab
You can import the list of beginning balance form an Excel spreadsheet or add balances one-by-one manually. To import the data, click the 
button on the toolbar.
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The Characteristic column is available if the Enable Item Characteristics option is selected on the Administration > Settings > Purchasing and Warehouses form. In this column, you can specify additional properties of the work item if the Use Characteristics option is selected for the item in its master record (see Items).
Use the Quantity column to enter the quantity of the work item in the unit of measure that is specified in the UOM column.
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In the Description field, cost object description appears as a string of appended attributes.
The Cost Object (create) dialog box
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You can link this balance with a project from the Projects list if the Project Costing functionality is turned on on the Administration > Settings > Project Costing form.
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In the GL Account column, make sure that the correct income account appears for recording the amount of already recognized revenue.
Use the Transaction Content column to enter the description for the journal entries.