Abstract
In the preceding report (1), I divided household into 10 groupes by the family types. Family types are as follows : Married couple with no children (C_0), married couple with children which are divided into 6 types according to the age of the eldest child (C_h, C_i, C_<k1>, C_<k2>, C_<k3>, C_m), widowed or divorced man or woman with children (B), single person (S) and complexed family including plural couples or member of 3 generation (CC). Every household changes their family types through their history, and from the survey on two communities, I found that the change ratio from a family type to other types in certain period are almost fixed, not concerned with the character of community, except the change of C_0 type. C_0 include 3 groupes of different ages, and each group has different change ratio, and each community include these groups in different ratio each other. Then I surveyed on the cause of changes in family types. There are 6 kind of cause, birth, growth, death, marriage or divorce and personal moving (immigration and emigration). Percentage of personal moving in all changes are 19 in appearance, but real moving are supposed lesser. So, natural cause and marriage occupies a large majority of cause of changes in family types. This fact suggest that the change ratio would be calculated using the statistical ratio of birth, death, marriage, divorce, etc. In the latter half of this report, I made trial to get the standardized change ratio on several family types.
