Hearing Aid Market

Probably a long shot, but anyone here know of any good resources for researching the hearing aid market? I’m just looking for general industry data and haven’t been able to find much, I guess because it’s such a small part of the medical device umbrella. Thanks

http://www.hearingresearch.org/Dr.Ross/why_do_HAs_Cost.htm Veterans Administration bought 300k units in 2003 - estimated 15% of market So 2mm units is at least a starting point