Lotus Notes Developement question

Greetings,

Is there any way to refresh specific fields only?
Actually I have two fields one Date/Time Editable named “Expire_Date” which is the expiry date of an equipment. And another computed field named Status. Now I want the Status field display “Expired” if the Date/Time field is passed from now. I used the follwoing formual in the Status field however it does not update automatically.

mVar := @Today;
nVar := @If(Expire_Date < mVar ; "License Expired" ; Expire_Date = mVar ; "License Expires Today" ; Expire_Date > mVar ; “License is still Valid” ; ” Invalid Expiration Date or Never Expires”);
oVar := @Text(Expire_Date);
@If(oVar = “” ; “License Never Expires or Invalid Expiration Date” ; nVar)

Thanks