1920	40.6	40.8	44.4	46.7	54.1	58.5	57.7	56.4	54.3	50.5	42.9	39.8
1921	44.2	39.8	45.1	47.0	54.1	58.7	66.3	59.9	57.0	54.2	39.7	42.8
1922	37.5	38.7	39.5	42.1	55.7	57.8	56.8	54.3	54.3	47.1	41.8	41.7
1923	41.8	40.1	42.9	45.8	49.2	52.7	64.2	59.6	54.4	49.2	36.3	37.6
1924	39.3	37.5	38.3	45.5	53.2	57.7	60.8	58.2	56.4	49.8	44.4	43.6
1925	40.0	40.5	40.8	45.1	53.8	59.4	63.5	61.0	53.0	50.0	38.1	36.3
1926	39.2	43.4	43.4	48.9	50.6	56.8	62.5	62.0	57.5	46.7	41.6	39.8
1927	39.4	38.5	45.3	47.1	51.7	55.0	60.4	60.5	54.7	50.3	42.3	35.2
1928	40.8	41.1	42.8	47.3	50.9	56.4	62.2	60.5	55.4	50.2	43.0	37.3
1929	34.8	31.3	41.0	43.9	53.1	56.9	62.5	60.3	59.8	49.2	42.9	41.9
1930	41.6	37.1	41.2	46.9	51.2	60.4	60.1	61.6	57.0	50.9	43.0	38.8
1931	37.1	38.4	38.4	46.5	53.5	58.4	60.6	58.2	53.8	46.6	45.5	40.6
1932	42.4	38.4	40.3	44.6	50.9	57.0	62.1	63.5	56.3	47.3	43.6	41.8
1933	36.2	39.3	44.5	48.7	54.2	60.8	65.5	64.9	60.1	50.2	42.1	35.8
1934	39.4	38.2	40.4	46.9	53.4	59.6	66.5	60.4	59.2	51.2	42.8	45.8
1935	40.0	42.6	43.5	47.1	50.0	60.5	64.6	64.0	56.8	48.6	44.2	36.4
1936	37.3	35.0	44.0	43.9	52.7	58.6	60.0	61.1	58.1	49.6	41.6	41.3
1937	40.8	41.0	38.4	47.4	54.1	58.6	61.4	61.8	56.3	50.9	41.4	37.1
1938	42.1	41.2	47.3	46.6	52.4	59.0	59.6	60.4	57.0	50.7	47.8	39.2
1939	39.4	40.9	42.4	47.8	52.4	58.0	60.7	61.8	58.2	46.7	46.6	37.8