"By definition, life expectancy tells you only when, out of a large group of people, half will have already died," said David Mendels, a certified financial planner and director of planning at Creative Financial Concepts. "You have no way of knowing which group you will be in."
4. Retiring too early. Many people are tempted to retire in their early 60s, but doing that can put considerable strain on a retirement portfolio, particularly for those who live into their 90s. By working a little longer, either at your current full-time job or at a part-time job during retirement, you can put off tapping your nest egg, giving your portfolio more time to compound, or draw down your savings more slowly.
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A part-time job during retirement, which may include consulting work or some other type of self-employment, can provide a source of funding for big-ticket items, such as travel.
Whether you retire later in life or work part-time during retirement, "anything you are not spending stays in your portfolio, not just for future use but also compounding into something more," said J. Christopher Boyd, a CFP and chief investment officer at Asset Management Resources.