These examples of population pyramids show not only the proportion of males and females in different age groups, but also marital status.
This cone-shaped pyramid is fairly typical of a 'pre-industrial' population. The lower steps are wider, indicating a larger proportion of young people. This results from higher fertility levels in a population without modern birth control methods. While most people marry, there are still a significant number of celibates in middle age, some of whom would be priests or members of religious orders. A few people live seperated from their spouses.
A broader pyramid, indicating better survivorship to middle age though there are clearly fewer males in these age groups than females. There are also fewer older celibates in this rural population.
In contrast to the two pyramids above, this one shows the modern urban and rural population of Ascoli. Notice the hour-glass shape with a much higher proportion of older people than in the historical examples. The narrower bands between 0 and 10 probably reflect smaller family sizes and delayed marriage (leading to fewer births). The 'waist' is probably an effect of absence due to migration, wheras the higher proportion of young adults may reflect the numbers of unemployed people in these age groups living at home. A steady proportion of people in most older age groups remain celibate. Many more people survive into old age, particularly women, which explains the number of older widows.
The last pyramid is typical of a modern rural community in a remote area. Rather than the cone shape of the early data, this is tending towards an inverted pyramid, with more elderly people than young. Lack of employment opportunities allied to better prospects in the towns and continental cities have meant that an inceasing number of Corsicans have left their natal villages. Some of those who left in their youth have returned to the village in retirement, thus contributing even more to the aging population. Few and small families have led to few children being resident. In the 30 years since this survey, the balance of old and young has become even more uneven.