Psychologists say they have have worked out that men and women can shop together for precisely 72 minutes before they start to fight.
At the crucial one hour and 12 minutes mark, retail experts say, couples should go their separate ways down the High Street or the shopping complex. Men will have had enough, while most women will then want to continue shopping for another 28 minutes.
The 72-minute claim has been calculated by Dr Tim Denison, a retail psychologist, who led research into the shopping habits of more than 2,000 people. Men and women were analysed on shopping trips, both separately and together, to pinpoint the moment at which tempers snap.
Adherents of the "men are from Mars, women are from Venus" theory, will be delighted to know that the gender differences in retail therapy go back to caveman instincts.
Dr Denison said most men act like "hunters" when shopping; they go out with a clear image of what they want, track it down and buy immediately.
"The thrill for men is in actually getting the thing they wanted," he said.
"When we measured their blood pressure as an indicator of excitement in shopping, men's peaked earlier than in women and went higher but faded as soon as they had actually bought the item.
"Women, on the other hand, act like gatherers; they take their time, stroll around, have less of an exact image of what it is they want, and are slower to peak in blood pressure.
"But their excitement levels stayed for much longer, around 15 minutes after purchase, showing that they derive more enjoyment overall."
Furthermore, the female of the species may not only be more deadly in nature but has more of a killer instinct for a bargain when shopping.
Dr Denison and his team found that women were more accurate in their mental estimates of how much products should cost and, on an average shopping trip got better bargains than men.Reuse content