This page is a register, not a census. Everything on the US map is something the collector saw for itself and can show a raw capture for. Nothing here is: these are facts from company filings, exchange announcements and the trade press, typed in by hand, each carrying the date it was true and how far it should be trusted. A count that has not been published is left blank rather than estimated, and “no evidence” means a search found nothing — which is a statement about the search, not about the chain.