| Total | Sewage disposal system | | 76.5 | 75.4 | 75.6 | 75.9 | 77.3 | 77.2 | 76.7 | 78.1 |
| Local sewerage | | 12.2 | 12.5 | 12.8 | 13.2 | 12.3 | 13.5 | 14.0 | 13.7 |
| No sewerage | | 11.3 | 12.1 | 11.6 | 10.9 | 10.4 | 9.3 | 9.3 | 8.3 |
| Single person aged 60 and over | Sewage disposal system | | 68.9 | 67.0 | 68.1 | 68.5 | 72.3 | 74.9 | 75.5 | 75.5 |
| Local sewerage | | 11.2 | 10.3 | 10.2 | 11.5 | 12.0 | 11.4 | 10.7 | 11.6 |
| No sewerage | | 19.9 | 22.7 | 21.7 | 20.0 | 15.7 | 13.7 | 13.8 | 12.9 |
| Single person aged under 60 | Sewage disposal system | | 81.3 | 77.4 | 79.9 | 80.1 | 79.9 | 80.4 | 81.2 | 86.2 |
| Local sewerage | | 8.2 | 9.0 | 7.6 | 8.3 | 6.6 | 6.1 | 7.6 | 5.4 |
| No sewerage | | 10.5 | 13.6 | 12.5 | 11.6 | 13.5 | 13.5 | 11.2 | 8.4 |
| Couple aged 60 and over without children | Sewage disposal system | | 69.6 | 68.4 | 69.5 | 66.7 | 70.5 | 68.7 | 67.6 | 69.2 |
| Local sewerage | | 15.7 | 14.8 | 15.8 | 16.7 | 15.6 | 21.7 | 22.6 | 19.7 |
| No sewerage | | 14.7 | 16.8 | 14.7 | 16.6 | 13.9 | 9.6 | 9.9 | 11.1 |
| Couple without children, at least one partner is aged under 60 | Sewage disposal system | | 76.4 | 76.2 | 76.3 | 78.7 | 80.8 | 82.2 | 80.6 | 80.2 |
| Local sewerage | | 14.3 | 15.3 | 16.0 | 15.1 | 14.1 | 11.5 | 13.1 | 13.7 |
| No sewerage | | 9.3 | 8.5 | 7.7 | 6.2 | 5.1 | 6.3 | 6.4 | 6.0 |
| Adult and child(ren) | Sewage disposal system | | 86.6 | 85.5 | 85.7 | 85.1 | 90.3 | 86.6 | 90.2 | 87.2 |
| Local sewerage | | 7.1 | 6.8 | 7.1 | .. | .. | .. | .. | .. |
| No sewerage | | 6.3 | 7.7 | 7.2 | .. | .. | .. | .. | .. |
| Couple with one child | Sewage disposal system | | 85.4 | 84.5 | 81.3 | 84.0 | 89.1 | 87.0 | 80.5 | 87.1 |
| Local sewerage | | 9.6 | 12.0 | 13.4 | 12.9 | .. | 9.6 | 16.1 | 10.4 |
| No sewerage | | 5.0 | 3.5 | 5.3 | .. | .. | .. | .. | .. |
| Couple with two children | Sewage disposal system | | 80.4 | 77.7 | 78.4 | 82.6 | 82.3 | 81.5 | 84.1 | 78.2 |
| Local sewerage | | 13.0 | 15.7 | 16.0 | 14.0 | 14.3 | 16.3 | 14.1 | 19.1 |
| No sewerage | | 6.6 | 6.6 | 5.6 | .. | .. | .. | .. | .. |
| Couple with three or more children | Sewage disposal system | | 66.6 | 67.2 | 58.8 | 62.3 | 66.5 | 64.3 | 66.1 | 65.4 |
| Local sewerage | | 22.0 | 17.1 | 25.5 | .. | .. | .. | .. | .. |
| No sewerage | | 11.4 | 15.7 | 15.7 | .. | .. | .. | .. | .. |
| Couple with minor and adult children | Sewage disposal system | | 75.3 | 74.8 | 72.5 | 70.8 | 70.4 | 69.7 | 67.9 | 69.8 |
| Local sewerage | | 15.9 | 18.1 | 19.7 | 21.0 | 21.4 | 24.1 | 25.9 | 25.0 |
| No sewerage | | 8.8 | 7.1 | 7.8 | 8.2 | 8.2 | 6.2 | 6.2 | 5.2 |
| Household consisting of two generations | Sewage disposal system | | 76.4 | 78.2 | 78.7 | 79.3 | 78.0 | 78.0 | 76.3 | 76.0 |
| Local sewerage | | 13.3 | 12.1 | 12.0 | 11.8 | 11.7 | 14.0 | 12.7 | 14.9 |
| No sewerage | | 10.3 | 9.7 | 9.3 | 8.9 | 10.3 | 8.0 | 11.0 | 9.1 |
| Other household | Sewage disposal system | | 75.0 | 75.5 | 75.8 | 71.1 | 70.8 | 69.3 | 68.7 | 73.6 |
| Local sewerage | | 12.9 | 14.4 | 12.4 | 19.3 | 15.9 | 19.8 | 21.3 | 17.9 |
| No sewerage | | 12.1 | 10.1 | 11.8 | 9.6 | 13.3 | 10.9 | 10.0 | 8.5 |