Recent change in prevalence of parent-child co-residence in Japan

"Co-residence of parents and grown-up (especially married) children has been one of the most important factors that affect the trends in household formation in recent Japan. This article reports the proportion co-residing...using a nation-wide large-sample household survey data set containing about 300,000 persons in each year.... The proportion of parents who co-reside with children...had remarkably decreased during the period 1975 to 1985, especially for younger elders regardless of their marital status.... On the contrary, the proportion co-residing of married children aged 20-39 with their parents had been constant or slightly rising...during the same period. These two opposite trends can be interpreted as follows: though the preference for co-residence has declined both for parents and for children, the child availability for parents has barely changed and the downward trend in preference has directly appeared [in] the proportion co-residing; while the parent availability for children has increased owing to the decrease in number of siblings to be balanced with the decreasing preference." (SUMMARY IN JPN)