| YEAR(S) | JAN | FEB | MAR | APR | MAY | JUN | JUL | AUG | SEP | OCT | NOV | DEC | ANN | |||||||||||||
| 1963 | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | 46.02 | c | 46.02 | |
| 1964 | 45.77 | 47.26 | b | 45.19 | g | ----- | z | ----- | z | ----- | z | ----- | z | 59.29 | 58.35 | 55.98 | 48.17 | 46.52 | 51.62 | |||||||
| 1965 | 45.66 | 46.12 | 48.50 | 49.85 | 50.77 | 55.37 | 58.69 | 61.65 | 59.24 | a | 56.61 | 52.72 | 45.85 | 52.59 | ||||||||||||
| 1966 | 46.60 | b | 44.81 | b | 46.68 | 51.00 | 52.03 | 57.53 | 59.34 | 60.08 | 59.90 | 54.97 | 51.42 | 48.37 | 52.73 | |||||||||||
| 1967 | 46.58 | 49.07 | a | ----- | z | 47.86 | p | 54.72 | k | 58.46 | b | 61.11 | 61.69 | b | 60.55 | 55.17 | d | 52.66 | b | 45.05 | 54.48 | |||||
| 1968 | 45.95 | a | 50.98 | 50.13 | 48.82 | 52.98 | a | 59.23 | 60.14 | b | 60.07 | b | ----- | z | 52.48 | g | 50.27 | b | 45.19 | b | 52.38 | |||||
| 1969 | 42.32 | a | 44.57 | m | 51.23 | t | 47.62 | b | 53.76 | 57.97 | 58.35 | 57.53 | 57.70 | b | 54.57 | h | 50.12 | 48.27 | 52.63 | |||||||
| 1970 | 47.79 | g | 48.95 | 48.52 | 46.52 | 53.89 | 57.12 | 59.37 | 58.56 | 57.07 | 51.44 | 51.00 | 47.53 | 52.72 | ||||||||||||
| 1971 | 46.59 | o | 45.61 | 43.32 | 47.21 | a | 50.81 | 54.47 | a | 58.26 | 61.48 | a | 59.47 | a | 52.74 | 48.47 | 43.71 | 51.41 | ||||||||
| 1972 | 43.37 | 47.30 | a | 50.15 | 48.29 | a | 53.11 | h | 56.61 | b | 59.53 | b | 60.39 | 57.30 | 54.66 | 49.92 | 43.26 | 51.89 | ||||||||
| 1973 | 45.05 | 49.79 | 46.42 | 49.35 | 53.45 | a | 56.41 | a | 58.00 | 56.94 | 58.55 | a | 53.48 | 48.32 | 48.89 | 52.05 | ||||||||||
| 1974 | 44.18 | 45.34 | 47.57 | c | 49.91 | b | 51.46 | e | 55.39 | b | 58.12 | a | 59.94 | 58.98 | b | 54.20 | h | 49.85 | d | 46.39 | d | 51.56 | ||||
| 1975 | 45.88 | g | 46.73 | b | 46.42 | 46.13 | 52.83 | a | 56.86 | b | 60.25 | a | 58.82 | 58.32 | b | 53.40 | a | 48.28 | 46.54 | d | 52.24 | |||||
| 1976 | 46.03 | b | 45.32 | d | 44.98 | 47.21 | f | 52.88 | o | 56.12 | d | 59.74 | h | 60.17 | j | 59.68 | h | 55.97 | l | 53.05 | h | 46.03 | m | 48.11 | ||
| 1977 | 46.68 | f | 50.43 | f | 45.46 | g | 49.29 | i | 51.11 | h | 57.58 | k | 59.18 | q | 60.13 | p | ----- | z | ----- | z | 49.33 | 49.82 | 49.58 | |||
| 1978 | 50.68 | 49.11 | 52.10 | 50.33 | 53.48 | 59.35 | 60.03 | 60.21 | 59.67 | 57.34 | 46.22 | 42.89 | 53.45 | |||||||||||||
| 1979 | 44.53 | 46.34 | 49.87 | 51.20 | 55.98 | 57.52 | 61.73 | 62.37 | 64.08 | 58.44 | 51.05 | 50.92 | 54.50 | |||||||||||||
| 1980 | 45.89 | 50.53 | 48.73 | 51.13 | 53.31 | 56.52 | 60.53 | a | 59.82 | 59.03 | 56.45 | 51.63 | 50.68 | 53.69 | ||||||||||||
| 1981 | 51.68 | 50.29 | 49.74 | 51.03 | 53.74 | 59.15 | 60.40 | 61.18 | 60.93 | 54.85 | a | 51.78 | 49.42 | 54.52 | ||||||||||||
| 1982 | 44.31 | 46.18 | 47.56 | 48.78 | 53.61 | 56.53 | 60.42 | 61.74 | 60.82 | 57.61 | 50.27 | 48.13 | 53.00 | |||||||||||||
| 1983 | 49.79 | 48.75 | z | 49.86 | t | 50.07 | w | 53.59 | b | 57.98 | 61.34 | 62.69 | 61.45 | 55.95 | 52.23 | 48.18 | a | 55.91 | ||||||||
| 1984 | 49.19 | 49.22 | 51.82 | 49.95 | 53.26 | 56.38 | 60.24 | 62.21 | 60.18 | 54.60 | 50.43 | 44.97 | 53.54 | |||||||||||||
| 1985 | 46.61 | 46.48 | 46.31 | 51.47 | 53.26 | 58.20 | 59.87 | 60.03 | 58.17 | 54.19 | 45.43 | 45.16 | 52.10 | |||||||||||||
| 1986 | 49.84 | 50.80 | 52.00 | 49.72 | 53.71 | 58.72 | 60.11 | 59.47 | 58.02 | 54.77 | 51.87 | 49.11 | 54.01 | |||||||||||||
| 1987 | 48.02 | 49.41 | 50.31 | 52.45 | 56.71 | b | 58.23 | b | 58.81 | 61.18 | 59.12 | 57.84 | 51.73 | 47.31 | 54.26 | |||||||||||
| 1988 | 46.77 | 48.17 | 48.29 | 51.60 | 53.11 | 57.30 | 60.98 | 59.23 | 58.52 | 57.48 | 50.48 | 46.82 | 53.23 | |||||||||||||
| 1989 | 45.24 | 42.20 | 47.68 | 53.60 | 53.89 | 58.12 | 60.74 | 62.13 | 58.05 | 54.23 | 50.67 | 47.71 | 52.85 | |||||||||||||
| 1990 | 47.21 | 44.91 | 48.87 | 51.60 | 54.16 | 57.15 | 62.31 | 61.27 | 61.57 | 54.03 | 49.30 | 41.16 | 52.80 | |||||||||||||
| 1991 | 46.15 | 51.73 | 46.31 | 49.20 | 51.76 | 56.37 | 61.47 | 61.05 | 61.98 | 57.47 | 50.87 | 47.06 | 53.45 | |||||||||||||
| 1992 | 48.21 | 51.34 | 52.29 | 54.13 | 57.52 | 58.82 | 62.03 | 62.10 | 60.23 | 57.32 | 50.48 | 45.61 | 55.01 | |||||||||||||
| 1993 | 43.85 | 47.09 | 51.32 | 51.25 | 55.32 | 58.37 | 61.11 | 61.60 | 58.60 | 56.53 | 48.22 | 47.26 | 53.38 | |||||||||||||
| 1994 | 48.87 | 45.93 | 49.39 | 50.60 | 55.24 | 56.42 | 59.02 | 62.11 | 59.90 | 54.52 | 44.63 | 45.79 | 52.70 | |||||||||||||
| 1995 | 50.27 | 50.55 | 48.84 | 49.27 | 53.84 | 56.32 | 61.53 | 60.66 | 60.35 | 55.84 | 52.03 | 50.58 | 54.17 | |||||||||||||
| 1996 | 47.63 | 49.02 | 48.81 | 51.92 | 52.76 | 56.72 | 58.77 | 59.15 | 57.98 | 53.53 | 49.85 | 48.35 | 52.87 | |||||||||||||
| 1997 | 46.98 | 47.12 | 48.37 | 49.73 | 56.56 | 57.57 | 62.15 | 61.73 | 61.65 | 54.81 | 52.33 | 46.97 | 53.83 | |||||||||||||
| 1998 | 50.68 | 48.96 | 49.11 | 49.08 | 52.56 | 56.77 | 59.65 | 61.15 | 58.67 | 53.74 | 49.37 | 44.71 | 52.87 | |||||||||||||
| 1999 | 45.92 | 46.23 | 44.77 | 49.12 | 51.26 | 55.88 | 56.94 | 60.43 | d | 59.88 | 57.94 | m | 52.96 | c | 48.55 | a | 51.99 | |||||||||
| 2000 | 48.85 | 51.14 | 47.55 | 52.03 | a | 53.39 | 55.73 | 57.15 | 56.08 | 54.65 | 53.18 | 51.05 | 53.77 | 52.88 | ||||||||||||
| 2001 | 55.97 | 46.32 | 49.34 | 48.23 | 54.26 | 56.27 | 59.05 | 59.56 | 57.85 | 55.48 | 50.63 | 47.32 | 53.36 | |||||||||||||
| 2002 | 45.11 | 47.98 | a | 46.13 | 49.68 | b | 51.81 | 56.22 | 60.50 | a | 59.67 | a | 57.53 | 52.40 | 51.75 | 49.44 | 52.35 | |||||||||
| 2003 | 51.06 | 47.05 | 50.71 | 49.47 | 53.98 | 58.02 | 61.16 | 61.23 | 59.12 | 58.10 | 49.20 | 48.15 | 53.94 | |||||||||||||
| 2004 | 48.10 | 48.48 | 50.13 | 52.85 | 54.74 | 57.52 | 60.81 | ----- | z | 58.65 | 54.56 | 49.48 | 49.11 | 53.13 | ||||||||||||
| 2005 | 47.77 | 48.80 | 51.47 | 50.02 | 55.32 | 56.73 | 60.35 | 59.34 | 57.07 | 53.71 | 49.60 | 48.84 | 53.25 | |||||||||||||
| 2006 | 49.98 | 46.89 | 46.55 | 49.43 | 53.06 | 57.67 | 60.05 | 57.98 | 56.80 | 54.16 | 49.98 | 48.06 | 52.55 | |||||||||||||
| 2007 | 43.58 | 46.77 | 49.69 | 49.05 | 52.84 | 55.12 | 59.76 | 61.03 | 57.00 | 54.05 | 49.43 | 45.10 | 51.95 | |||||||||||||
| 2008 | 44.40 | 45.57 | 44.92 | 46.92 | 53.02 | 54.22 | 57.58 | 60.35 | 56.83 | 54.50 | 52.23 | 44.63 | 51.26 | |||||||||||||
| 2009 | 46.24 | 46.57 | 46.47 | 48.38 | 52.03 | 56.70 | 59.50 | 59.31 | 59.97 | 54.98 | 49.62 | 44.02 | 51.98 | |||||||||||||
| 2010 | 51.05 | 50.25 | 48.08 | 48.20 | 51.40 | 56.55 | 58.39 | 59.53 | 59.10 | 55.24 | 47.93 | 48.81 | 52.88 | |||||||||||||
| 2011 | 47.79 | 44.95 | 48.19 | b | 47.60 | 51.11 | 56.80 | 59.72 | a | 61.55 | a | 59.21 | b | 56.39 | 47.85 | 44.82 | 52.16 | |||||||||
| 2012 | 45.95 | 46.27 | c | 45.92 | 50.38 | 52.27 | 55.42 | 60.19 | 59.29 | 56.33 | 54.58 | 52.18 | 45.61 | 52.03 | ||||||||||||
| 2013 | 44.31 | 45.79 | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | 45.05 | |||
| Period of Record Statistics | ||||||||||||||||||||||||||
| MEAN | 47.17 | 47.70 | 48.42 | 49.87 | 53.41 | 57.00 | 59.90 | 60.32 | 59.01 | 55.15 | 50.11 | 47.07 | 53.09 | |||||||||||||
| S.D. | 2.69 | 2.15 | 2.17 | 1.81 | 1.55 | 1.21 | 1.31 | 1.47 | 1.72 | 1.64 | 1.85 | 2.36 | 0.86 | |||||||||||||
| SKEW | 0.77 | 0.04 | -0.13 | 0.16 | 0.54 | -0.05 | -0.36 | -0.72 | 0.30 | 0.18 | -0.86 | 0.09 | 0.31 | |||||||||||||
| MAX | 55.97 | 51.73 | 52.29 | 54.13 | 57.52 | 59.35 | 62.31 | 62.69 | 64.08 | 58.44 | 52.96 | 53.77 | 55.01 | |||||||||||||
| MIN | 42.32 | 42.20 | 43.32 | 46.13 | 50.77 | 54.22 | 56.94 | 56.08 | 54.65 | 51.44 | 44.63 | 41.16 | 51.26 | |||||||||||||
| NO YRS | 46 | 47 | 44 | 44 | 44 | 47 | 46 | 46 | 46 | 43 | 48 | 49 | 35 | |||||||||||||