"There is a huge gulf between how much people expect to spend in retirement and how much they actually will, and this is before costs such as long-term care have been factored in.
"This pre-retirement period is the most important when it comes to ensuring you have a solid financial plan in place to guarantee you can live the lifestyle you want while not running out of funds."
He added the challenge of funding a financial secure retirement had become ever greater because of the improvements in longevity.
Mr Cowan explained: "If we continue to see growth in average life spans, the costs of tomorrow are likely to be even greater than the data in our report suggests."
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