Nathan Winograd of the No Kill Advocacy Center, a promoter of no-kill shelters, says that overpopulation is a myth and logical fallacy, which many animal control agencies use to avoid criticism for high numbers of killings and low numbers of adoptions. Winograd says that traditional shelters kill animals primarily out of habit and convenience, even when space is available for the animals. He says that using trap-neuter-return (TNR) for stray and feral cats, his organizations have been able to save all healthy and treatable animals, and raise their save rates to at least 90% of all impounded animals. He says there are enough homes for all the homeless animals: "Based on the number of existing households with pets who have a pet die or run away, more homes potentially become available each year for cats than the number of cats who enter shelters, while more than twice as many homes potentially become available each year for dogs than the number of dogs who enter shelters." Winograd says his methods, including TNR for stray and feral cats, and comprehensive changes in animal control, rescue, shelter and community efforts have succeeded in saving all healthy and treatable animals, amounting to at least 90% of all impounded animals. Winograd says that hundreds of No Kill Communities have been created across the U.S., and they are increasing in number throughout the world. In October 2014, the website "Out the Front Door" documented 212 communities in the U.S. saving more than 90% of impounded animals.