Every six months, I archive my Sent Items folder. This may sound geeky, but it’s one of the most productive and satisfying activities I do all year. Why do I love getting rid of old email? The main answer is that there is no more straightforward measure of activity in this digital age than the Sent Items folder. Every email I personally wrote is an effort to advance some aspect of my personal or professional life.

These are messages to clients, advice to friends, requests to vendors or follow-ups to prospects. Each email represents me trying to get something done. When I look at my total Sent Items for half a year, I feel pretty great.

The numbers in particular are fantastically motivating. From July 1, 2010 to December 31, 2010, I wrote a total of 4,849 emails. Some are only a few words and others run for several paragraphs. They are spread across over a thousand individual recipients (although the largest percentage of emails were inside the company.) That’s a ton of work, and it’s easy to see where the time went: into communicating essential ideas over email.

You can go farther down the analysis. Of those emails, I initially flagged 1,567 for follow-up. That’s a feature of my email program, Microsoft Outlook, which I use when I think I might need to check again with the recipient about the content of my email. I don’t use the flagging feature for people inside my company naturally, and I don’t use it for messages that are sent just to personal contacts. Therefore, those 1,567 emails represent current or potential business opportunities!

Emails tend to pile up as a sequence of replies. I do my best to keep a flag on only the most current email in a follow-up chain, so that means that although I marked 1,500+ emails at one time, I processed most of those conversations to a resolution.

There were only 143 emails remaining. That means I chased down 1,424 individual interactions to get a satisfactory reply! That number is encouraging. It means that I’m getting answers, advancing opportunities and building business in a very real way over email.

That’s not to say that my Sent Items data is the only measure of my work. And in fact, I actually do the archiving six months later (to keep recent sent email handy), so the information is not current. Nevertheless, this quick checkup feels great. I know I’m working hard and what I have to show for it.

Finally, archiving old email provides a satisfying finality to days gone by. If a conversation is older than six months, then I need to accept that it’s no longer happening. There’s a catharsis in letting go of old email. Messages I sent in the distant past will probably never receive replies. If I need to reach that person still, it’s time to write a new message, or better yet, to pick up the phone.