I think a significant portion of the yorkies that go missing are due to theft. I live in a city where small breeds are VERY popular, and often stolen...that's why I would never leave my fur baby out in my back yard unless I'm there to supervise them (much to my future-in-laws dismay). It's difficult to supervise them 24 hours a day, 7 days a week...but I'm sure everyone here tries their absolute best to ensure that their fur babies are as safe as can be (indoors and outdoors).