"The median number of Groupons sold to each Groupon customer (someone who has bought anything): 1."<p>"The median number of Groupons sold to each person on Groupon’s mailing list: 0."<p>The median doesn't seem like a fair way to measure either of these. Obviously there the distribution of Groupons sold is skewed, so the mean is likely to be much higher than the median. It would probably paint a clearer picture to say "Of the 25% of people on the mailing list that bought something, half bought 1 groupon, and the other half bought on average 3.6 groupons." (numbers are made up)