I had also heard conversations of age 71 to 75. I don't know what that magic number is. Perhaps as we have further studies in here....
One of the things I have noted from self-employed individuals—business owners—is that their retirement date tends to be later anyway. When Canadians are asked how old they feel versus their chronological age, they say they feel 15 years younger than they truly are. The age 71 limit has been around for many, many years. If we accept the fact that we are living longer, to age 93, as my colleague's mother has, perhaps 71 is not appropriate any longer.