Age Difference Between Man And Woman At Marriage

A friend of mine showed me a video of a prom that her cousin attended. The video was nice. All boys and girls were about 19 years old and formally dressed. 

A thought struck me and I voiced it to her. Girls at that age are more mature than boys and hence how do girls tolerate being with a boy of the same age. 

She replied that this was utter nonsense. She continued that most girls are quite comfortable with boys of the same age. Maybe what I said could be true in India. It certainly didn't apply in Europe. 

Obviously I couldn't let myself be contradicted. So I searched on the net and found some interesting data on age at the time of 1st marriage. The rest of what I say below is based on that data (and I have talked only about Europe).

http://en.wikipedia.org/wiki/Age_at_first_marriage

The age at which people get married has been rising across the world. This increase is attributed to higher education, wanting to be independent before getting married. But the fact remains that no matter when people get married (early 20s to mid 30s), the age of the man is higher than the woman's by about 2 to 4 years.

I would have assumed that countries that were geographically adjacent to each other would have data similar / close to each other. And this is generally the case. But there are exceptions: People in Spain got married later (M:34/F:33) than Portuguese (M:28/F:26). Incidentally, the difference in age between men and women at the time of marriage seems to be lowest for Spain among all European countries.

I found a similar difference between Moldova (M:25/F:22) and Romania (M:31/F:27), between Germany (M:33/F:30) and Poland (M:28/F:25) and between Finland (M:31/F:28) and Estonia (M:28/F:25). An average German man married at the age of 33 and a man from neighboring Poland at the age of 28. Surprising to see so much of a difference (about 3-6 years) between neighboring countries in the age at which people marry.

The pattern seems to be that people in countries in Eastern Europe (having a border with Russia) marry earlier than those in the west. Finland is an exception.