cfsearch scores related to date

I'm setting up a search collection of news articles and want to return results by score, except that it would be good to change the weighting to score newer articles higher.  News from 5 years ago may not be as relevant as news from last week or last month.  I'm guessing there is nothing built-in for this.  So I can look into weighting the score.  But I was wondering if there is any good logic for doing this?

One thought was to round off the scores to the nearest integer, and then sort by score + date.  This would bump newer stories that have similar scores.  Or just bump the score a certain amount based on how new it is?  It may just need trial & error, but suggestions would be welcome.