According to the report, called '050 A Fresh Perspective', by Interpublic agencies Weber Shandwick and FutureBrand, the majority of consumer advertising is wrongly concentrating on 20- to 40-year-olds and young families.
Instead, it should be turning its attention to over 50-year-olds who, it is claimed, currently hold around 80% of the UK's disposable income.
According to the report, this amounts to some £196bn in spending power, but the majority of advertising and marketing activity leaves the over-50s "patronised and invisible".
The report also calls on media and advertising firms to invest in employing more staff and key creative figures from this age group.
David Yelland, senior vice-chairman at Weber Shandwick and former editor of The Sun, said: "Are the over-50s some kind of homogenous group with the same likes, dislikes and disposable income?
"Of course not, they are as varied, creative and vibrant as any other demographic grouping into which the communications industry somewhat arrogantly seeks to segment society."
The report called for more PR, media and marketing activity such as Mick Jagger's appearance on the front cover of Saga magazine, which better define the age group's lifestyle rather than reinforce cliches of silver surfers and coach tour holidays.
The report has been timed for 2005 because the first of the baby boomer generation turns 50 this year. Famous figures that celebrate their half-centuries this year include the actors Bruce Willis and Billy Bob Thornton, Radio 2 DJ Steve Wright and the model Iman.
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