CW's affiliates were formerly affiliated with UPN or The WB, with very few having been independent stations or affiliates of other networks prior to joining the network; a notable exception was Las Vegas affiliate KVCW, which had been a fairly successful independent before joining The CW. Although it was generally understood that The CW was a merger of UPN and The WB, the new network's creation was not structured as a merger in the legal sense. Rather, it was one new network launching at the same time that two others shut down, although it did assume certain programming content, operations, and management from its predecessors. As such, The CW was not obligated by existing affiliations with The WB and UPN; it had to negotiate from scratch with individual stations. As a result, in several markets, the CW affiliation is on a local station different from either the former WB and UPN stations (for example, the CW affiliation in Las Vegas ended up on KVCW, instead of former WB affiliate KVMY or now-defunct former UPN affiliate KTUD-CA). The network has also affiliated with some digital subchannels, usually those launched by a local Big Four affiliate as a new service, in several other markets – especially if fewer than six commercial television stations existed at the time of affiliation, requiring The CW to carry its programming on a subchannel by default (for example, The CW opted to affiliate with a subchannel of WKRC-TV in Cincinnati – which has only five commercial full-power stations – instead of former WB affiliate WSTR-TV, which instead became an affiliate of MyNetworkTV). Because of the availability of "instant duopoly" digital subchannels that will likely be easily available on cable and satellite, and the overall lack of a need to settle for a secondary affiliation with shows aired in problematic timeslots that would subject the timeshifted programs to lower average viewership in certain markets, both The CW and MyNetworkTV launched with far greater national coverage than that enjoyed by UPN and The WB when they both launched in January 1995. UPN, for several years, had affiliation gaps in the top 30 markets, and by 2005 managed to cover only 86% of the country. This resulted in secondary affiliations with other networks and the resulting diluted ratings when programs were shown out of their intended timeslots, or the lack of the program airing at all (a problem experienced by