Not to rest at all!  Dr. Steve Sheppard and others continues to follow
this.  Out of the entire US bee population of perhaps 4 million hives, the
vast majority of queens are produced each season from a relative handful of
breeder queens, by only a few producers.  

I think these numbers are closer to the actual:

> In studies conducted in 1993-1994 and in 2004-2005, U.S. commercial queen producers self-reported the production of close to 1 million queens for sale from around 600 and 500 queen "mothers," respectively (Schiff and Sheppard, 1995, 1996; Delaney et al., 2009). 

Sammataro, Diana, and Jay A. Yoder, eds. Honey bee colony health: challenges and sustainable solutions. CRC Press, 2011.

             ***********************************************
The BEE-L mailing list is powered by L-Soft's renowned
LISTSERV(R) list management software.  For more information, go to:
http://www.lsoft.com/LISTSERV-powered.html