OK, here is what I know about lost sales posting and where it comes from. Over the years I have collected data from thousands of dealerships, all types and kinds. The average (and that is a word I disdain) is 2-3 per man per day. I maintain a select base (not for statistical purposes, but for what can be done when the best are at it) of 105 dealerships; the best of the best. They are getting 5-8 per man per day.
The real answer is "post all lost sales" and dont' worry about the numbers. The posting must become part of the culture. The countermen are pretty intelligent; they just need a reason for doing the posting, teach them why and measure it every month. Post the lost sales posted daily, weekly, or monthly on a bulletin board. Remember, it is not the existence of lost sales that is a negative indicator of performance. It is the absence of lost sales that is negative. Track and trend them long term and you will usually see an increase in them, month by month. Never pay someone extra to post them; I saw this done once and it was a disaster. Hope this helps.
Mike Nicholes www.partsconsulting.com