Update date calculation when viewing report

Update date calculation when viewing report

So I am using the Zoho.currentdate to calculate the days a "listing" has been live. Here is the Deluge Script:

input.Days_on_market = ((zoho.currentdate - input.Date_listed)) / (1000 * 60 * 60 * 24);

It does not seem to be updating when you pull up a record in view. Is there a way to do that? The other option is to schedule it to update every record on a schedule, but that seems overly taxing and not the right way to do it. Suggestions?

Colin