YEAR(S) | JAN | FEB | MAR | APR | MAY | JUN | JUL | AUG | SEP | OCT | NOV | DEC | ANN | |||||||||||||
1949 | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | 61.66 | 58.40 | 58.76 | 59.61 | i | |||
1950 | 58.32 | c | 58.68 | 57.85 | 58.53 | 59.23 | a | 60.72 | 62.31 | 63.42 | 63.19 | a | 62.08 | 61.33 | 58.45 | 60.34 | ||||||||||
1951 | 58.15 | 57.42 | c | 59.13 | 58.47 | 59.48 | k | 61.50 | 62.84 | 62.89 | 63.42 | 62.00 | 59.13 | 57.69 | 60.24 | a | ||||||||||
1952 | 56.16 | 57.71 | 56.77 | 57.16 | a | 58.60 | 60.50 | 62.90 | 62.87 | 61.35 | 62.76 | 60.23 | 58.24 | 59.60 | ||||||||||||
1953 | 58.42 | 57.96 | 57.44 | 59.52 | 60.84 | 61.05 | 62.37 | 63.90 | 62.37 | 61.60 | 59.70 | 58.89 | 60.34 | |||||||||||||
1954 | 57.77 | 58.50 | 58.06 | 61.23 | 61.00 | a | 62.47 | 62.66 | 63.74 | 62.87 | 62.52 | 61.85 | 57.66 | 60.86 | ||||||||||||
1955 | 56.40 | a | 56.18 | 56.76 | 57.68 | 58.31 | 59.72 | 59.90 | 60.42 | 60.97 | 60.89 | 59.65 | 59.35 | 58.85 | ||||||||||||
1956 | 59.44 | 57.05 | ----- | z | 58.98 | 59.81 | 60.35 | 62.34 | 63.52 | 62.85 | 62.74 | 60.77 | 59.82 | 60.70 | a | |||||||||||
1957 | 57.35 | 55.61 | 56.40 | 58.75 | 59.87 | 62.13 | 63.40 | 63.58 | 65.02 | 64.37 | 61.95 | 58.35 | 60.57 | |||||||||||||
1958 | 57.13 | 58.14 | 56.79 | 58.57 | 59.94 | 61.80 | 63.29 | 64.55 | 63.28 | 62.26 | 61.42 | 58.69 | 60.49 | |||||||||||||
1959 | 59.95 | 57.12 | 59.18 | 60.73 | 60.98 | 62.81 | a | 64.12 | a | 64.48 | 64.33 | 63.69 | 60.95 | b | 57.09 | c | 61.29 | |||||||||
1960 | 56.47 | 57.72 | 59.18 | 59.20 | 61.26 | 62.12 | 63.05 | 63.71 | 63.33 | a | 63.35 | 59.43 | 58.90 | a | 60.64 | |||||||||||
1961 | 58.39 | 58.39 | 57.94 | 58.93 | 60.03 | 61.37 | 61.73 | 62.50 | 61.77 | 62.63 | 59.19 | a | 56.60 | 59.95 | ||||||||||||
1962 | 57.77 | 57.68 | 57.10 | 60.18 | 59.71 | 61.33 | 61.82 | 62.00 | 61.70 | 61.05 | 58.92 | 57.88 | a | 59.76 | ||||||||||||
1963 | 58.84 | b | 61.98 | c | 60.05 | 60.08 | 59.79 | 60.88 | a | 62.18 | 62.16 | b | 63.97 | 62.44 | 60.70 | 60.29 | 61.11 | |||||||||
1964 | 58.12 | a | 56.95 | 57.68 | 58.00 | 58.77 | 62.75 | 62.73 | 62.40 | 62.03 | 61.32 | 59.95 | 60.56 | 60.11 | ||||||||||||
1965 | 58.58 | 54.84 | 56.84 | 59.27 | 61.81 | 60.67 | 62.55 | 62.63 | 63.88 | 62.50 | 61.33 | 56.66 | 60.13 | |||||||||||||
1966 | 57.06 | 57.07 | 58.85 | 58.47 | 61.55 | 61.55 | 62.02 | a | 63.66 | 63.75 | 62.81 | 60.95 | 59.55 | 60.61 | ||||||||||||
1967 | 56.76 | 58.09 | 58.95 | 59.52 | 61.74 | 62.67 | 64.21 | 64.11 | 63.93 | 63.47 | 59.76 | a | 58.82 | 61.00 | ||||||||||||
1968 | 57.64 | b | 59.55 | a | 59.53 | a | 59.90 | 61.92 | 62.18 | 63.53 | 63.84 | 64.15 | 63.90 | 62.45 | 59.63 | 61.52 | ||||||||||
1969 | 56.77 | 57.05 | 57.05 | 57.47 | 60.41 | b | 62.62 | a | 63.03 | 63.13 | a | 62.33 | 62.98 | 60.47 | 59.63 | 60.25 | ||||||||||
1970 | 59.85 | 57.34 | 57.60 | 58.71 | b | 61.50 | d | 61.95 | 62.10 | 63.05 | b | 62.64 | a | 62.47 | 61.20 | 56.94 | 60.45 | |||||||||
1971 | 58.24 | 58.21 | 57.82 | 59.17 | 58.92 | 60.63 | 61.92 | 62.16 | 62.62 | b | 61.42 | 61.43 | 56.44 | 59.92 | ||||||||||||
1972 | 56.30 | a | 56.20 | f | 59.88 | b | 57.97 | a | 59.52 | b | 61.41 | c | 61.55 | 63.63 | 63.17 | a | 63.26 | 60.09 | a | 58.52 | 60.48 | a | ||||
1973 | 58.13 | 55.39 | 57.08 | 57.15 | 58.10 | 60.45 | 62.71 | 62.70 | a | 62.25 | b | 61.55 | a | 60.46 | b | 59.62 | a | 59.63 | ||||||||
1974 | 60.81 | 58.63 | a | 59.58 | a | 59.98 | a | 60.55 | 61.73 | b | 61.90 | a | 63.60 | 63.07 | a | 62.48 | 59.50 | 58.03 | a | 60.82 | ||||||
1975 | 56.76 | b | 57.21 | 56.13 | 57.10 | 57.66 | 59.22 | 60.71 | c | 61.73 | a | 61.29 | b | 61.02 | 60.09 | a | 58.35 | 58.94 | ||||||||
1976 | 57.68 | 55.93 | 57.66 | 56.52 | 58.26 | 59.18 | 60.88 | a | 62.27 | a | 63.50 | 62.00 | b | 59.79 | a | 58.39 | c | 59.34 | ||||||||
1977 | 57.97 | 58.65 | a | 56.63 | 59.18 | 59.52 | a | 61.71 | a | 62.57 | j | 61.21 | c | ----- | z | 62.83 | a | 60.70 | 57.85 | a | 59.62 | b | ||||
1978 | 58.17 | b | 57.02 | f | 58.42 | 60.08 | e | 61.94 | 61.93 | 63.10 | 64.61 | 63.29 | a | 63.33 | a | 62.04 | c | 56.88 | a | 61.25 | a | |||||
1979 | 56.38 | g | 56.76 | c | 57.77 | e | 59.44 | e | 60.23 | c | 61.00 | c | 63.64 | b | 64.61 | 65.28 | 64.74 | 61.75 | 61.00 | a | 61.48 | a | ||||
1980 | 59.00 | 61.15 | b | 57.89 | 61.15 | d | 62.10 | 61.90 | 63.94 | 63.82 | 64.47 | 63.39 | 62.05 | 61.24 | 61.84 | |||||||||||
1981 | 59.55 | 58.93 | 58.24 | 60.02 | 61.35 | a | 63.43 | 63.77 | 65.16 | 64.57 | 62.52 | a | 60.95 | 58.18 | a | 61.39 | ||||||||||
1982 | 57.81 | 59.80 | a | 57.93 | b | 59.33 | 60.02 | a | 63.97 | a | 64.23 | 65.00 | 63.50 | 63.02 | 61.88 | 60.13 | 61.38 | |||||||||
1983 | 58.54 | c | 58.42 | b | 58.35 | a | 58.50 | b | 59.02 | 61.10 | d | 61.89 | 62.87 | a | 63.32 | 61.44 | 62.02 | a | 60.38 | a | 60.49 | |||||
1984 | 59.35 | a | 59.69 | 61.33 | a | 60.30 | 61.90 | 62.13 | 63.63 | 63.10 | 63.91 | a | 64.94 | 61.57 | 58.98 | 61.74 | ||||||||||
1985 | 58.20 | c | 59.08 | d | 56.38 | b | 57.93 | b | 58.09 | n | 62.38 | a | 63.95 | 65.08 | a | 64.15 | 63.06 | 61.72 | 59.95 | 61.08 | a | |||||
1986 | 59.37 | a | 60.23 | b | 62.45 | b | 60.04 | b | 62.14 | c | 62.46 | d | 64.74 | b | 66.47 | b | 65.85 | c | 64.48 | b | 62.34 | a | 60.18 | a | 62.56 | |
1987 | 58.32 | c | 57.70 | a | 57.42 | f | 59.30 | b | 58.91 | d | 62.60 | a | 63.61 | 65.24 | b | 65.78 | c | 63.81 | 61.67 | c | 60.88 | a | 61.62 | a | ||
1988 | 60.27 | 59.82 | a | 59.45 | b | 59.58 | d | 62.48 | c | 63.20 | 63.35 | 64.47 | a | 64.53 | a | 64.76 | 63.42 | d | 60.79 | 62.18 | ||||||
1989 | 58.35 | a | 58.80 | a | 60.26 | b | 59.83 | 61.42 | 63.23 | d | 63.48 | b | 64.27 | 63.13 | 64.57 | c | 61.84 | b | 59.61 | c | 61.57 | |||||
1990 | 58.92 | 55.44 | d | 58.34 | c | 60.73 | b | 60.69 | d | 61.52 | a | 63.65 | a | 64.60 | 64.52 | b | 62.42 | a | 62.35 | c | 59.05 | a | 61.02 | |||
1991 | 58.48 | 60.64 | 57.50 | 59.70 | 61.50 | 62.07 | a | 63.57 | b | 65.60 | a | 65.17 | 64.10 | a | 63.63 | d | 59.69 | 61.80 | ||||||||
1992 | 58.15 | 58.17 | 58.85 | a | 59.36 | i | 63.64 | i | 63.53 | a | 64.60 | a | 64.85 | a | 66.33 | 65.92 | e | 63.55 | i | 60.44 | 62.32 | c | ||||
1993 | 58.73 | c | 57.30 | a | 59.26 | 60.57 | 60.52 | 63.22 | 63.44 | 64.83 | a | 65.15 | d | 64.15 | a | 60.71 | a | 58.00 | a | 61.32 | ||||||
1994 | 57.77 | 59.87 | a | 58.55 | 60.03 | 61.10 | 62.87 | 65.73 | 65.37 | 65.07 | 63.79 | 60.52 | a | 58.60 | 61.60 | |||||||||||
1995 | 58.26 | 59.46 | 60.34 | 60.42 | 61.11 | 62.40 | 63.48 | 64.07 | a | 64.07 | 63.08 | 62.88 | 61.32 | 61.74 | ||||||||||||
1996 | 59.77 | a | 58.00 | a | 58.92 | 62.17 | 63.73 | 64.38 | 64.27 | 65.00 | 64.32 | 64.69 | 62.63 | 59.56 | 62.29 | |||||||||||
1997 | 59.73 | a | 58.98 | a | 59.90 | 60.13 | 62.06 | 63.48 | 64.55 | a | 64.77 | 65.17 | 64.16 | 61.57 | 58.47 | 61.92 | ||||||||||
1998 | 58.48 | 58.71 | 60.03 | 58.43 | 59.24 | 61.95 | 62.94 | 64.23 | 63.28 | 62.98 | 60.85 | 58.31 | 60.79 | |||||||||||||
1999 | 58.58 | a | 57.38 | 57.55 | 58.50 | 60.87 | a | 61.25 | 62.52 | 62.89 | c | 62.05 | a | 62.85 | a | 60.13 | 59.12 | a | 60.31 | |||||||
2000 | 56.74 | 59.48 | 58.97 | a | 58.28 | 61.76 | 62.43 | a | 63.54 | c | 64.58 | a | 63.72 | 63.71 | 61.73 | b | 60.28 | b | 61.27 | |||||||
2001 | 59.40 | a | 58.16 | c | 58.53 | a | 59.23 | 60.84 | 62.48 | 64.03 | b | 65.18 | 64.60 | a | 63.02 | a | 63.22 | a | 59.18 | a | 61.49 | |||||
2002 | 59.66 | 57.20 | a | 59.17 | b | 62.26 | c | 62.68 | c | 63.02 | b | 64.52 | d | 64.83 | b | 63.29 | a | 64.09 | c | 62.32 | m | 58.43 | x | 62.07 | b | |
2003 | 59.46 | q | 59.00 | o | 60.62 | c | 59.34 | b | 62.11 | 63.19 | a | 64.84 | 64.84 | 63.97 | 64.18 | 61.27 | 60.83 | a | 62.52 | b | ||||||
2004 | 59.89 | i | 60.98 | c | 60.89 | c | 60.73 | 63.50 | c | 63.20 | 64.24 | b | 65.55 | 65.08 | 64.35 | 62.59 | a | 59.98 | a | 62.83 | a | |||||
2005 | 60.38 | c | 58.64 | c | 60.52 | 60.18 | 63.72 | b | 62.79 | a | 64.61 | 64.12 | b | 64.97 | a | 62.29 | 62.00 | 61.13 | a | 62.11 | ||||||
2006 | 59.23 | a | 58.06 | b | 59.48 | 58.71 | a | 59.87 | 62.87 | 64.06 | 64.89 | 63.67 | 64.30 | a | 63.92 | 60.58 | a | 61.64 | ||||||||
2007 | 58.90 | 57.50 | b | 59.48 | 58.66 | b | 60.92 | 62.65 | 64.52 | 63.53 | 64.11 | b | 62.48 | a | 62.03 | 59.28 | b | 61.17 | ||||||||
2008 | 57.05 | b | 58.34 | 59.72 | a | 60.80 | b | 63.80 | a | 62.33 | 64.14 | b | 63.77 | 62.82 | b | 62.65 | 62.00 | b | 59.50 | b | 61.41 | |||||
2009 | 58.00 | a | 57.07 | g | 56.48 | a | 58.61 | b | 62.69 | b | 63.21 | a | 63.97 | a | 65.31 | 63.63 | 64.91 | d | 62.06 | c | 61.48 | a | 61.85 | a | ||
2010 | 59.77 | e | 58.50 | a | 58.17 | b | 59.31 | d | 61.57 | a | 62.54 | c | 62.91 | b | 63.58 | 63.14 | e | 62.86 | b | 61.33 | 60.52 | b | 61.18 | |||
2011 | 60.00 | h | 60.81 | a | 59.91 | b | 60.22 | a | 61.30 | a | 61.97 | a | 61.79 | e | 63.16 | b | 62.07 | a | 61.60 | 59.81 | d | 58.60 | b | 61.02 | a | |
2012 | 59.06 | e | 58.02 | c | 56.77 | a | 56.67 | r | 59.09 | c | 60.29 | f | 60.62 | a | 61.41 | b | 60.34 | b | 61.45 | c | 57.85 | f | 57.85 | e | 59.40 | c |
2013 | 57.16 | b | 55.52 | b | 56.85 | 58.94 | c | 61.84 | c | 60.98 | a | 62.69 | d | 63.07 | c | 62.94 | c | 62.92 | s | 60.75 | f | 58.15 | k | 60.00 | c | |
2014 | 56.94 | o | 60.23 | o | 59.08 | l | 60.41 | m | 60.94 | n | 61.26 | m | 63.79 | n | 63.76 | n | 64.41 | m | 64.19 | r | ----- | z | ----- | z | ----- | z |
2015 | ----- | z | 60.89 | s | 57.78 | o | 59.35 | q | 59.30 | u | 61.93 | w | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z |
Period of Record Statistics | ||||||||||||||||||||||||||
MEAN | 58.34 | 58.18 | 58.50 | 59.32 | 60.78 | 62.02 | 63.13 | 63.79 | 63.56 | 63.03 | 61.18 | 59.14 | 60.89 | |||||||||||||
S.D. | 1.10 | 1.49 | 1.39 | 1.18 | 1.47 | 1.09 | 1.15 | 1.20 | 1.24 | 1.14 | 1.21 | 1.27 | 0.87 | |||||||||||||
SKEW | -0.01 | 0.12 | 0.36 | 0.05 | -0.01 | -0.48 | -0.47 | -0.42 | -0.20 | 0.15 | -0.06 | -0.16 | -0.37 | |||||||||||||
MAX | 60.81 | 61.98 | 62.45 | 62.26 | 63.80 | 64.38 | 65.73 | 66.47 | 66.33 | 65.92 | 63.92 | 61.48 | 62.56 | |||||||||||||
MIN | 56.16 | 54.84 | 56.13 | 56.52 | 57.66 | 59.18 | 59.90 | 60.42 | 60.34 | 60.89 | 58.40 | 56.44 | 58.85 | |||||||||||||
YRS | 60 | 60 | 62 | 62 | 61 | 63 | 63 | 64 | 63 | 64 | 61 | 63 | 48 |