What I've Done With My Physics Degree Part 2: The Lifeguard Question...

Since I was 16, I've spent my summers on the Jersey shore as a ocean rescue lifeguard.  Those close enough to me know my fondness for the job.  What's not to like about sitting in the sun, working out, and looking at plenty of girls.  And the people you work with are funny, and happy.  However, much like the Jersey shore, many of the people I know there are consumed with getting laid. 
Well, the way the job works is that you sit on a stand all day with a partner.  Now conversation topics vary from politics, to philosophy, to ridiculous games of would you rather.  One day, the topic of the conversation got to how slutty everyone down there was and how easy it was to score.  At one point my partner goes, "Dude I saw a couple banging in a car at 5PM yesterday.  D'you have any idea how many people are getting laid right now on this island alone?!"

So being the person I am I took this as a challenge.  Except I tried estimating the number of people who are having sex in the world at any given instance.  The basic strategy is based upon something I learned in physics class.  Enrico Fermi is a Italian physicist and a genius and was famously known for being able to ball-park the answers to random questions quickly and accurately.  Basically if you estimate the numbers of the contributing factors, you tend to overestimate as much as you underestimate and they balance out to give a good answer.  So I plan to do the same in this case.

I started with just the following assumption.  There are 6.6 billion people in the world.

Now for the fun stuff.

1.) You are physically able to be sexually active for roughly 2/3's of your life.
That means 4.4 billion people are currently physically capable of sexually activity.

2.) Now I'd say a little more than half of the people in the world are either in a relationship or environment to have sex (like college or the jersey shore).  Remember a huge portion of the population abstains for religious reasons....
So that means roughly 2.5 billion people are in a position to get some.

3.) I once heard that the average married couple has sex once a week (try not to think of your parents as you read that...or grandparents).  Now lets think about the people in the right environments (like college or the jersey shore) who probably are slightly less successful.  A nice round number would be to say when you are in the right situation, you have sex 1 out of every 10 days.

4.) Now every sexual encounter takes about 20 minutes (don't kid yourself, you're no Sting).
That means for 20 mins out of every 10 days you are bumping uglies. 
20 mins out of (10 days*24 hours *60 mins) you have your "O face" on.
So 1/720th of the time you're in the position to get laid, you actually are.

5.) 2.5 billion people are spending 1/720th of their time doing it. 
This translates to roughly 3.5 million people in the world having sex at any instant. 
Any instant.  Like this one.  And you're online reading my stupid blog...

But if you want to feel better about yourself that's only 0.05% of the population, so you're in good company.