Period	Persons
1967-01-01	14822362
1972-01-01	16611970
1977-01-01	18478909
1982-01-01	20767511
1987-01-01	23260094
1992-01-01	25569662
1997-01-01	27632321
2002-01-01	29311443
2007-01-01	30667086
2012-01-01	32521143