if [enddate] <> "1/1/1901" then
    if ([Contract Status]="FiT" or [Contract Status]="CSL Takeover" or [Contract Status]="Name Transfer-Death" or [Contract Status]="Orig owner sold house to FiT") then
         Duration.Days([enddate] - [fitcommencement]) + 1 
    else 
        0
else
    0