For sold to each customer, I believe the median is a better measure. See http://blog.agrawals.org/2011/08/11/groupon-s-1-full-of-hole/ http://blog.agrawals.org/

For sold to each customer, I believe the median is a better measure. See http://blog.agrawals.org/2011/08/11/groupon-s-1-full-of-hole/ http://blog.agrawals.org/2011/08/11/groupon-s-1-full-of-hole...