Access VBA Programming - Performance

    Dim cn As ADODB.Connection
    Dim rs As New ADODB.Recordset
    Set cn = CurrentProject.Connection
    Dim rs2 As New ADODB.Recordset

    rs.Open "CrewList", cn, adOpenKeyset, adLockOptimistic, adCmdTableDirect

    Do While Not rs.EOF

        ' Following method is much faster than using DCount("CrewCertID", "CrewCert",  where) 2 times per loop 
        rs2.Open "select * from crewcert where crewID = " & rs!CrewID & " AND certificateID = 105", cn
        Do While Not rs2.EOF

            rs!FRC = 0
            If rs2!ValidTo >= Date Then
                rs!FRC = 1
            ElseIf IsNull(rs2!ValidFrom) And Not IsNull(rs2!ValidTo) Then
                rs!FRC = 1
            End If
            rs2.MoveNext

      Loop
      rs2.Close
      rs.Update
      rs.MoveNext

    Loop
    rs.Close