Year	1970	1979
Sweden	46.9	57.4
Netherlands	44	55.8
Norway 	43.5	52.2
Britain	40.7	39
France	39	43.4
Germany	37.5	42.9
Belgium	35.2	43.2
Canada	35.2	35.8
Finland	34.9	38.2
Italy	30.4	35.7
United States	30.3	32.5
Greece	26.8	30.6
Switzerland	26.5	33.2
Spain	22.5	27.1
Japan	20.7	26.6