is "Portal Site of Official Statistics of Japan" (external site) where you can browse statistics tables and database.

Summary of First Basic Complete Tabulation Results 

Link to statistical tables

Released on 31 October, 2006

Population pyramid of Japan	5. Housing
1. Total population	6. Foreigners
2. Population by Age	Attached Table1. Indicators of Japan
3. Marital Status	Attached Table2. Indicators by prefecture
4. Households	Attached Table 3. Population by Age and Sex