month	1967	1968	1969	1970	1971	1972	1973	1974	1975	1976	1977	1978	1979	1980	1981	1982	1983	1984	1985	1986	1987	1988	1989	1990	1991	1992	1993	1994	1995	1996	1997	1998	1999	2000	2001	2002	2003	2004	2005	2006	2007
Janaury	13.3	12.9	12.7	11.9	14.5	13.6	18	DNA	11.5	11.9	12.9	11.4	13.7	12.5	12.3	14.5	11.5	DNA	13.9	14.3	DNA	14.8	12.7	16.2	13	13.5	13.3	15.4	12.7	14.2	12.7	14.4	15	14.6	14.2	13.9	14.7	13.6	13.4	18.2	14.6
Frebuary	15	15.6	17.3	13.8	14.4	14.5	16.3	DNA	14.3	15.4	14.9	14	14.6	14.1	16.5	13.2	14.2	DNA	15.1	15.9	DNA	16.7	15.8	14.3	17.6	13.6	15.9	15.2	14.3	16.1	13.6	16.4	20	14.5	17.6	17.2	15.3	15.9	17.5	19.1	13.7
March	16.8	19.1	19.1	18.8	18.6	20.2	19.7	DNA	19.5	18.9	19.7	16.7	18.9	18.2	17.8	17.7	19.3	DNA	21.1	18.9	DNA	19.1	18.8	17	19.5	21.8	17.7	19.4	19.7	20.3	19	17.7	21.7	19.1	19.7	19.5	18.4	21.6	20	20	18.8
April	DNA	22.4	21.9	21.6	18.5	21.5	23.7	DNA	23.6	21.4	20.1	20.5	21.9	23.7	19.7	21.6	20.4	21.5	22.8	21.5	20.9	22.5	22.8	21.2	22.2	24	21.3	22.4	23.3	22.9	19.3	21.5	25	22.7	22.5	21.6	22.6	21.9	22.7	21.7	22.6
May	23.9	23.3	22.6	23.1	20.8	23.1	21.5	DNA	23.6	21.2	20.4	21.9	24	22.5	21.8	23.8	21.5	22	22.7	21.6	24.4	23.6	23.7	22.5	24	22.4	23.1	24.1	25.6	24.6	23.3	23.7	24.2	23.8	23	22.6	23.6	23.6	23.4	23.3	24
June	24.7	22.1	23	22.1	22.4	23.6	22.2	DNA	23.4	22	22.8	23	23.4	22.4	23.4	23.3	24.4	23.5	25	23.9	22.9	23.7	24	25	23.9	24.9	24.3	24.6	23.8	23.7	24.3	25.8	24.1	24.1	24.2	23.9	24.1	23.9	24.7	24.2	23.6
July	DNA	24	22.7	22.3	22.4	23	22.9	DNA	22.1	22.6	22.9	22.4	22.9	22.8	22.8	23.5	23.9	22.4	22.6	23.1	22.7	23.9	23.2	23.9	24.5	23.8	24.3	25	23.6	23.2	24.5	23.9	24	24.5	24.6	23.8	24	23.2	23.9	24.6	23.5
August	24.7	22.6	22.4	22.8	21.8	22.8	22.6	DNA	22.8	21.3	22.7	23.2	22.6	22.6	23.6	23.6	23.6	23.9	25.1	24	22.3	23.7	23.9	24.1	24	23.8	23.7	24.6	24.2	23.8	24.1	23.3	23.3	23.9	24.3	23.8	24.2	24.5	24.3	24.5	24.1
Spetemberr	23.8	23.1	21.8	22	21.9	21.5	21.5	DNA	20.9	21.2	22.1	21.5	21.5	22.1	22.6	22.5	23.1	21.5	22.1	22.3	23	23.5	23	23.6	23.6	23.6	23.1	23.6	23.3	23.6	23.2	24.2	23.7	22.8	23.8	23	23.6	23	24.4	23.5	23
October	21.1	19.3	19.2	19.8	20.5	20.2	19.4	DNA	20.4	19.3	18.8	19.7	19	19.9	20.9	19.7	DNA	21.8	19.8	20.4	20.6	22.3	22	20.8	22.1	20.8	21.9	21.5	21.8	21.6	19.8	23.4	21.7	22.1	22	21.1	22.1	20.6	21.6	22.2	21.9
November	15.9	17.1	16.5	16	16.7	17.8	16.3	DNA	15.5	16.4	16.6	15.7	17.7	17.3	17.3	16.4	17.3	16.9	16.7	16.9	18.3	18.1	17.1	19.3	17	17.5	18	17.4	18.3	18.6	18.1	20	18.6	18.4	18.9	18.4	18.4	17	18.2	18.1	DNA
December	15.7	14.5	13.9	15.6	14	17.2	13.1	DNA	13.4	15	12.6	15.3	13.1	15.3	14	14.2	15	DNA	15.8	DNA	16.2	15.4	14.8	15.8	14.7	14.3	16.1	15.1	14.7	15.8	14.4	16.5	15.4	15.3	15	15.3	14.9	15.3	16.4	15.7	16