Is this a 'sum' field, or a 'summary' field?
Thanks for your response. Its a "Sum" field.
There is no such thing as a "sum" field. When you look at the field in Manage | Database | Fields, it's field type will be either summary or calculation (in which case you might have a sum() function defined for that calculation). We need to know the details of what you have defined (not just the type, but what options you selected for that type), in which table you defined this field and what exact relationship you have defined between the layout's table and the portal.
And we also need to know if there is any portal filter set up on the portal.