I run two queries for the daily number of reports for bextra and avandia:
https://api.fda.gov/drug/event.json?search=receivedate:[20050101+TO+20050430]+AND+brand_name:bextra&count=receivedate
https://api.fda.gov/drug/event.json?search=receivedate:[20101001+TO+20101031]+AND+brand_name:avandia&count=receivedate
The avandia search produces the results I expect, the bextra search does not. The bextra search is run for the months prior to its withdrawal. I do not believe that there wasn't a single report in those months. Can anyone clarify what's going on?