Dew, you could attribute Walgreen’s 4.9% year over year December pharmacy sales increase to the increase in the number of weekdays, however, I attribute it to the increase in the number of comparable stores. The number of comparable Walgreen stores increased about 10% during the past year. (There were 5580 total stores as of Nov 2006 and 6139 total stores as of Nov 2007 resulting in a 559 increase of comparable stores in Nov 2008 over Nov 2007). There were 7,123 total stores in Nov 2008.
Perhaps, I am making too much of this semantic difference and the numbers actually refer to a per store metric. If so, then stores open less than a year would need to have had negative sales numbers; i.e.the numbers given for total sales from all stores are $6.1B in Dec 2008 vs $5.5B in Dec 2007. Thus, sales/store in 2008 were $0.86M/store vs $0.90M/store in 2007.
Irrespective of the attribution, the sales increase is not as impressive as it might first appear.