MS Access 2003字段值[]

Question

One of the fields in the MS Access Form has the value as =[OpenThisMonth]+[ClosedThisMonth] in the Design View. I tried figuring out what these values stand for. It is not a database field. It is not present in the form itself as any other field. It is not a macro too. I do not understand the syntax either. Does anyone know what it might represent.

If I click on the control source of the field. I get this - Link

EDIT

SELECT DISTINCTROW clients.*,
                   businesscodes.businesstype,
                   firstname + "" + lastname AS HContact,
                   brokers.brokername,
                   brokers.contact
FROM   ((clients
         LEFT JOIN businesscodes
                ON clients.businesscode = businesscodes.businesscode)
        LEFT JOIN hamiltoncontacts
               ON clients.hamiltoncontact = hamiltoncontacts.hamiltoncontact)
       LEFT JOIN brokers
              ON clients.brokernumber = brokers.brokernumber
ORDER  BY clients.clientname; 

Answer 1

Answering my own question here --

There was a subform which had fields by the name OpenThisMonth and ClosedThisMonth