For pre-retirees who are still building the nest egg, this analysis can provide insights about what to expect in the future.

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One advantage is that money left unspent in accounts can be rolled over to the following year, building a nest egg to cover the deductible.

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Not only will you start building up a nest egg, you'll have more money for things that do make you happy, like handbags or trips to Spain.

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Older couples who thought they were building a secure nest egg are discovering that a chunk of the equity they thought they had will be eaten up IRS depreciation recapture rules that impose a tax on the accumulated depreciation deductions they took for all those years.

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Some use the same investment strategy for both building and tapping a nest egg.

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The hard truth is that building a proper nest-egg takes much more ambitious savings than virtually any 401(k) plan envisions.

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Building on earlier research, which showed that egg cells from rabbits could be fertilised in test tubes when sperm was added, Edwards developed the same technique for humans.

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