<font face="Verdana, Arial, Helvetica, sans-serif" size="2">Originally posted by JS:
What would also be interesting is the average number of trips per person excluding those who never fly or fly very rarely (say, once every five years). There are a lot of people who don't fly. I estimate 50% of the population of 262 million never or rarely flies, which implies 1.5 round trips per person remaining.</font>
From
ABC news, "More than 85% of the American public flies infrequently if at all. More than seven in 10 can be described as infrequent fliers, flying once or twice a year or less; and 14 percent have never flown. Another 14 percent fly at least once every few months."
So, excluding people who have never flown, you have 191,685,912 round trips/(.86&mult;262,803,000) = .85 round trips per American who has ever flown.
I'm not sure how to extend this farther. I don't believe that number of miles flown is the same between frequent and infrequent fliers, and these stats are vague and a little self-serving (is it meaningful to know how frequently people travel of people who travel at least every 90 days? The answer will be at least 4!).