| | 1959 | 1970 | 1979 | 1989 | 1999 |
| Number of families | 866,3 | 1076,9 | 1247,2 | 1519,4 | 1687,5 |
| by number of family members: |
| one member | 95,4 | 120,3 | 144,5 | 138,0 | 130,6 |
| two members | 141,2 | 142,8 | 165,3 | 203,2 | 138,7 |
| three members | 151,1 | 144,0 | 161,2 | 200,1 | 213,6 |
| four members | 143,0 | 153,2 | 191,1 | 293,6 | 350,1 |
| five members | 119,0 | 137,0 | 168,1 | 252,3 | 346,3 |
| six members | 93,3 | 128,0 | 141,4 | 181,9 | 230,9 |
| 7 and more members | 123,3 | 251,6 | 275,6 | 250,3 | 277,3 |
| average number of family members | 4,5 | 5,1 | 5,1 | 4,8 | 4,7 |
| by percent to total |
| Number of families | 100 | 100 | 100 | 100 | 100 |
| by number of family members: |
| one member | 11,0 | 11,2 | 11,6 | 9,1 | 7,7 |
| two members | 16,3 | 13,3 | 13,3 | 13,4 | 8,2 |
| three members | 17,5 | 13,4 | 12,9 | 13,2 | 12,7 |
| four members | 16,5 | 14,2 | 15,3 | 19,3 | 20,8 |
| five members | 13,7 | 12,7 | 13,5 | 16,6 | 20,5 |
| six members | 10,8 | 11,9 | 11,3 | 11,9 | 13,7 |
| 7 and more members | 14,2 | 23,3 | 22,1 | 16,5 | 16,4 |