Wow. That is an open ended question!
Let me ask you why this is info you are interested in? What bearing does this have on your selling or buying decisions?
That said, Bellevue moved from being a coal depot from Newcastle in the early part of the century to a business center in the early 1980's. Many existing homes in older neighborhoods were built in the late 40's early 50's. Much of Bellevue was built in the 60's much more in the 70's get my drift? A better question might be what is the average age of a home withina specific neighborhood. Which still beggs the question of why is this a relevant question?