In a classic study of human mating from 1989, David Buss surveyed 37 cultures across 6 continents and found that in every culture in question, men preferred to marry younger women (2.66 years younger on average) and women preferred to marry older men (3.42 years older on average).
In addition, Buss collected actual age differences at marriage for 27 of the 37 cultures, and across the board men normally married women who were younger than themselves.
(Couples who were the same age were not included in this analysis). For sample, there were significantly more couples in which the man was older as opposed to the woman being older, 133 and 56 pairs, respectively.
Conversely, women are drawn to older men since they typically have greater resources.
And in a 1993 study that analyzed over 1,000 personal ads, researchers found that women typically sought older men, and men typically sought younger women.Similarly, in a 1994 study using a nationally representative sample of single Americans younger than 35, the results revealed that women were significantly more willing than men to marry someone older by five years; conversely, men were significantly more willing than women to marry someone who was younger by five years.