The formula for wedded bliss

REUTERS

PERFECT PAIRING: Actor Paul Newman and his wife of 50 years Joanne Woodward.

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Finally, the secret of Paul Newman and Joanne Woodward's 50-year marriage can be revealed: they got the numbers right.

Newman was five years older than Woodward, a differential which gets a big tick from researchers at the Geneva School of Business who have come up with a formula for the perfect union.

After analysing 1074 couples aged 19 to 75, the researchers concluded that the wife should be five years younger than her husband. The partners should be from the same cultural background and the woman should be more intelligent than her spouse.

How much more intelligent? The wife should be at least 27 per cent brighter than her husband and should hold a degree, while he should not. Perhaps unsurprisingly, marrying a divorcee reduced the chance of wedded bliss.

''If people follow these guidelines in choosing their partners they can increase their chances of a happy, long marriage by up to 20 per cent,'' said Nguyen Vi Cao, whose study is published in the European Journal of Operational Research.

Paul Newman was a divorcee (no tick there) and it would be rude to speculate if his wife was smarter than him. But the magic five-year differential can also be observed in the long-lasting marriages of the Queen and the Duke of Edinburgh and John and Janette Howard.

One Sydney couple, Panchali and Suhrid Sheth, also appear to have the numbers. She is five years younger than her husband, comes from a similar cultural background and is (sometimes) the more intelligent partner - or so she says.

The Sheths have been married for 26 years. ''I've always believed women are a little bit more mature than men so having that age difference balances it out - that extra five years brings him to my level,'' Mrs Sheth said.

But Anne Hollonds, the vice-president of Relationships Australia, said the findings did not hold true for all modern relationships. The ones that last ''tend to be more equal''.

with agencies

FORMULA FOR WEDDED BLISS:

-Husband should be five years older than his wife.

-Wife should be at least 27 per cent more intelligent than her husband.

-Spouses should share the same cultural background.

- with agencies

- © Fairfax NZ News