YEAR(S) | JAN | FEB | MAR | APR | MAY | JUN | JUL | AUG | SEP | OCT | NOV | DEC | ANN | |||||||||||||
1958 | ----- | z | ----- | z | ----- | z | ----- | z | 60.61 | 63.00 | 62.35 | 65.35 | 67.88 | 63.48 | 57.13 | 56.34 | 62.02 | d | ||||||||
1959 | 53.05 | 51.09 | 56.06 | 58.47 | 58.24 | 60.45 | 62.62 | a | 64.40 | 62.45 | 63.74 | 58.48 | a | 52.81 | 58.49 | |||||||||||
1960 | 47.82 | 51.67 | 55.50 | 56.53 | 57.95 | 62.07 | a | 61.82 | 61.19 | 62.20 | 59.52 | 53.77 | 50.19 | 56.69 | ||||||||||||
1961 | 53.73 | 52.61 | 52.10 | 55.98 | a | 57.03 | 62.77 | 63.26 | 63.98 | 63.85 | 61.08 | 54.70 | 49.77 | 57.57 | ||||||||||||
1962 | 50.25 | a | 50.93 | 50.67 | a | 57.30 | 56.76 | 59.43 | 59.03 | 63.79 | 60.55 | 62.11 | 56.70 | 53.16 | 56.72 | |||||||||||
1963 | 47.92 | 57.12 | 51.56 | 53.70 | 58.16 | 59.85 | 61.90 | 62.40 | 65.40 | 62.19 | 54.88 | 51.58 | 57.22 | |||||||||||||
1964 | 48.62 | a | 51.31 | 51.00 | 53.24 | a | 55.16 | 60.18 | 61.90 | 62.92 | 61.85 | 62.55 | 52.70 | 52.19 | 56.14 | |||||||||||
1965 | 51.39 | 50.55 | 52.92 | 56.25 | 56.82 | 59.20 | 61.50 | 64.94 | 62.42 | 64.08 | a | 55.93 | 47.34 | 56.95 | ||||||||||||
1966 | 48.73 | 49.30 | 53.27 | 58.52 | 58.03 | 61.18 | 61.55 | a | 62.76 | 64.23 | 62.34 | 56.78 | 51.63 | 57.36 | ||||||||||||
1967 | 51.26 | 53.21 | 52.81 | 50.43 | 59.42 | 58.63 | 62.50 | a | 62.71 | 66.25 | 64.29 | 58.03 | 48.26 | 57.32 | ||||||||||||
1968 | 49.87 | 56.95 | 55.16 | 55.45 | 58.06 | 60.90 | 61.90 | a | 66.74 | l | 64.00 | 59.39 | 53.78 | 47.77 | 56.66 | a | ||||||||||
1969 | 50.15 | 49.05 | 52.35 | a | 53.70 | 58.40 | 61.67 | 61.50 | 61.06 | 62.97 | 59.29 | 57.90 | 52.21 | 56.69 | ||||||||||||
1970 | 51.94 | 54.21 | 54.79 | 53.62 | 59.68 | a | 60.92 | 63.57 | x | ----- | z | 65.02 | a | 59.89 | 57.55 | 50.50 | 56.81 | b | ||||||||
1971 | 52.52 | b | 51.38 | 53.76 | 53.25 | 56.55 | 60.55 | b | 61.03 | 64.34 | b | 65.38 | 57.37 | 53.35 | 46.81 | 56.36 | ||||||||||
1972 | 49.53 | 54.71 | 56.82 | a | 55.83 | 58.24 | 59.75 | j | 64.11 | 64.02 | 63.22 | 61.18 | 54.70 | 48.19 | 57.32 | a | ||||||||||
1973 | 48.94 | 54.52 | 51.32 | 56.55 | 58.50 | 62.34 | a | 60.90 | a | 60.52 | 62.12 | 60.12 | a | 52.61 | b | 51.27 | 56.64 | |||||||||
1974 | 49.40 | 51.27 | 54.26 | 55.00 | 56.31 | 59.08 | 61.56 | 61.95 | 61.93 | 62.83 | b | 55.43 | 49.97 | 56.58 | ||||||||||||
1975 | 51.53 | 52.88 | 54.10 | a | 52.82 | 58.45 | a | 60.37 | k | 61.92 | 62.56 | 62.78 | 58.48 | 54.20 | 52.34 | b | 56.55 | a | ||||||||
1976 | 53.24 | 52.66 | 51.73 | c | 54.36 | b | 57.94 | 61.15 | c | 61.82 | a | 64.98 | 63.05 | 62.80 | d | 59.52 | 52.97 | 58.02 | ||||||||
1977 | 50.34 | 54.39 | 50.68 | 55.92 | 56.04 | c | 59.89 | c | 61.44 | m | 63.13 | d | 62.78 | a | 59.34 | b | 54.77 | 52.80 | a | 56.37 | a | |||||
1978 | 51.44 | 52.06 | a | 56.45 | a | 53.29 | a | 59.94 | f | ----- | z | 63.55 | 62.58 | 65.00 | 60.79 | 52.82 | ----- | z | 57.55 | c | ||||||
1979 | 48.86 | i | 48.38 | o | 54.13 | l | 56.04 | b | 59.90 | 60.64 | b | 62.87 | 63.03 | 66.10 | 62.95 | b | 55.20 | 52.67 | e | 59.93 | c | |||||
1980 | 53.12 | b | 55.80 | a | 53.65 | 56.67 | a | 56.58 | 59.65 | 63.16 | 62.02 | 63.27 | 60.95 | 56.08 | 54.13 | 57.92 | ||||||||||
1981 | 55.19 | 54.46 | a | 53.47 | 56.28 | a | 57.88 | b | 64.97 | k | 60.60 | k | 63.05 | 63.16 | a | 59.39 | 58.70 | 52.87 | a | 57.44 | b | |||||
1982 | 47.52 | a | 54.25 | d | 52.62 | c | 56.24 | a | ----- | z | 59.28 | c | 61.56 | 62.85 | d | 63.90 | e | 62.38 | a | 54.84 | b | 50.57 | c | 56.91 | a | |
1983 | 52.55 | 54.76 | a | 54.57 | b | 55.88 | 59.60 | b | 62.00 | b | 65.48 | e | 67.72 | b | 70.07 | c | 65.88 | b | 58.27 | d | 55.97 | a | 60.23 | |||
1984 | 54.05 | b | 54.80 | d | 58.71 | b | 56.45 | b | 59.96 | f | 57.67 | c | 62.75 | a | 65.60 | 68.29 | b | 59.95 | b | 53.83 | c | 49.98 | 58.37 | a | ||
1985 | 48.74 | b | 51.48 | b | 50.46 | c | 57.06 | c | 55.84 | 61.98 | c | 62.96 | f | 62.95 | a | 63.59 | a | 60.52 | g | 50.48 | f | 54.66 | b | 56.31 | c | |
1986 | 56.98 | e | 56.21 | d | 58.82 | f | 56.98 | b | 60.02 | e | 62.98 | a | 63.41 | b | 64.75 | a | 61.20 | b | 61.81 | b | 58.89 | b | 54.14 | b | 59.76 | a |
1987 | 51.24 | f | 55.60 | d | 56.84 | c | ----- | z | 61.60 | b | ----- | z | 62.62 | b | 64.73 | a | 64.82 | b | 65.32 | c | 57.23 | 51.89 | d | 60.07 | c | |
1988 | 53.70 | d | 57.62 | a | 57.84 | 60.23 | f | 60.26 | d | 62.39 | b | 64.98 | 65.71 | 64.22 | a | 63.47 | a | 58.10 | a | 54.39 | d | 60.25 | a | |||
1989 | 52.03 | 52.23 | 57.78 | a | 59.37 | c | 58.66 | c | 61.70 | 60.08 | ----- | z | 62.44 | c | 59.63 | a | 56.83 | 51.95 | 57.52 | a | ||||||
1990 | 48.40 | a | 48.66 | c | 54.32 | a | 59.54 | b | ----- | z | 62.18 | 62.39 | c | 63.73 | 63.42 | 61.40 | b | 55.82 | 47.02 | 56.99 | a | |||||
1991 | 51.08 | 56.31 | a | 51.55 | c | 54.65 | 56.15 | 57.90 | 61.39 | 64.03 | 63.59 | a | 61.87 | a | 57.82 | 52.38 | b | 57.39 | ||||||||
1992 | 52.37 | 56.86 | a | 57.08 | 61.18 | 61.98 | 62.47 | 65.45 | b | 64.30 | a | 63.98 | 64.45 | 57.22 | 50.09 | d | 59.79 | |||||||||
1993 | 50.92 | a | 52.24 | a | 58.37 | 58.33 | a | 62.03 | b | 63.53 | a | 63.18 | c | 65.88 | c | 63.93 | 64.48 | 57.03 | 52.97 | a | 59.41 | |||||
1994 | 54.30 | a | 52.52 | b | 57.52 | a | 57.52 | a | 59.29 | b | 61.67 | 61.50 | 64.35 | d | 64.93 | a | 62.13 | a | 52.72 | c | 50.55 | 58.25 | ||||
1995 | 54.64 | b | 57.61 | a | 56.86 | b | 58.15 | 58.97 | 62.38 | b | 66.43 | a | 65.16 | c | 65.88 | a | 63.82 | c | 61.72 | 54.26 | 60.49 | |||||
1996 | 53.23 | a | 56.26 | d | 56.65 | d | 59.72 | 60.02 | d | 60.88 | 63.70 | a | 62.47 | a | 62.27 | b | 60.72 | a | 55.75 | b | 53.48 | c | 58.76 | |||
1997 | 52.34 | c | 52.37 | b | 55.98 | c | 57.54 | c | 63.21 | b | 62.43 | c | 63.84 | c | 66.98 | c | 67.34 | b | 61.85 | a | 59.23 | d | 50.72 | a | 59.48 | |
1998 | 53.53 | b | 51.40 | h | 55.12 | e | 54.50 | a | 56.94 | d | 62.04 | b | 63.61 | d | 64.52 | a | 63.76 | e | 58.69 | b | 54.27 | b | 48.77 | c | 57.79 | a |
1999 | 51.54 | f | 51.23 | d | 50.95 | c | 54.36 | e | 55.62 | a | 58.45 | a | 61.38 | b | 63.10 | b | 62.11 | b | 61.72 | a | 56.33 | a | 51.32 | a | 56.96 | a |
2000 | 51.59 | d | 55.10 | e | 53.88 | a | 58.09 | b | 59.65 | d | 62.40 | d | 61.24 | 61.72 | a | 63.69 | d | 59.21 | c | 51.55 | 53.07 | c | 57.60 | |||
2001 | 49.31 | b | 51.23 | b | 55.65 | a | 52.41 | c | 60.91 | b | 61.40 | d | 61.60 | 61.90 | b | 61.83 | c | 61.05 | c | 56.79 | b | 51.12 | e | 57.10 | ||
2002 | 48.48 | e | 54.63 | b | 53.95 | c | 56.40 | d | 57.87 | d | 61.28 | e | 63.63 | a | 64.48 | d | 65.02 | e | 61.10 | b | 59.65 | d | 53.72 | f | 58.77 | a |
2003 | 57.95 | b | 53.84 | c | 56.72 | d | 55.79 | b | 60.53 | b | 63.88 | f | 64.83 | a | 68.29 | c | 68.23 | b | 64.74 | d | 55.55 | b | 54.67 | b | 60.10 | a |
2004 | 51.50 | a | 51.82 | a | 59.71 | b | 57.82 | b | 59.28 | a | 61.03 | a | 63.98 | b | 65.05 | b | 64.89 | b | 60.29 | c | 54.45 | a | 52.38 | c | 58.52 | |
2005 | 52.28 | b | 55.75 | d | 57.75 | e | 55.38 | b | 59.93 | b | 60.64 | b | 63.03 | b | 62.60 | a | 61.55 | a | 59.76 | b | 58.43 | 53.98 | d | 58.42 | ||
2006 | 52.21 | b | 54.40 | b | 50.88 | c | 55.74 | c | 58.98 | a | 62.29 | a | 64.03 | a | 62.95 | 62.39 | b | 61.43 | d | 55.83 | a | 51.69 | d | 57.73 | ||
2007 | 48.10 | b | 52.50 | c | 56.30 | c | 54.98 | e | 57.72 | a | 59.61 | c | 62.65 | a | 63.32 | a | 63.56 | d | 59.78 | a | 56.24 | a | 48.78 | a | 56.96 | |
2008 | 49.62 | e | 51.41 | 52.82 | c | 54.40 | d | 57.18 | 60.24 | c | 62.17 | d | 62.90 | b | 63.61 | b | 62.54 | c | 58.62 | d | 49.62 | c | 57.09 | |||
2009 | 53.83 | d | 52.73 | b | 52.55 | c | 56.00 | c | 58.22 | d | 61.93 | b | 61.66 | b | 64.39 | d | 63.55 | a | 59.85 | e | 54.75 | b | 50.43 | c | 57.49 | |
2010 | 53.39 | c | 54.06 | c | 53.40 | b | 53.70 | e | 55.75 | a | 60.28 | c | 60.50 | 61.03 | a | 63.54 | d | 60.87 | 54.47 | 52.86 | b | 56.99 | ||||
2011 | 53.38 | a | 50.42 | c | 53.96 | s | 55.40 | d | 56.66 | b | 59.45 | b | 62.09 | b | 61.21 | 63.36 | e | 63.70 | c | 53.39 | b | 49.82 | 57.17 | a | ||
2012 | 52.39 | 52.70 | a | 54.42 | a | 56.00 | 57.21 | 59.27 | 60.92 | g | 61.55 | b | 60.60 | e | 62.09 | n | 58.31 | c | 50.61 | 56.31 | b | |||||
2013 | 50.81 | 50.17 | a | 55.18 | 57.10 | 59.89 | 63.46 | r | 62.45 | 63.65 | 64.43 | 59.08 | 56.15 | 51.29 | 57.29 | a | ||||||||||
2014 | 56.24 | 53.80 | 57.77 | a | 58.38 | 61.69 | 60.50 | 64.74 | 65.79 | 65.62 | 64.90 | 58.30 | 54.66 | 60.20 | ||||||||||||
2015 | 56.02 | 58.34 | 59.52 | 56.32 | 58.39 | 62.15 | 66.45 | 67.76 | 67.18 | 66.31 | 53.53 | 49.37 | 60.11 | |||||||||||||
2016 | 53.47 | 58.40 | 57.32 | 59.53 | 59.95 | 61.67 | 60.82 | 62.19 | 63.85 | 61.46 | e | 57.07 | c | 49.78 | v | 59.61 | a | |||||||||
2017 | 50.81 | 54.73 | 57.15 | a | 57.83 | 59.35 | a | 61.55 | b | 62.23 | k | 64.32 | f | 68.32 | 62.92 | a | 58.65 | 52.82 | 58.41 | b | ||||||
2018 | 53.87 | h | 53.14 | 54.79 | b | 56.32 | 58.02 | c | 59.80 | t | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | 55.57 | h | ||
Period of Record Statistics | ||||||||||||||||||||||||||
MEAN | 51.74 | 53.49 | 54.69 | 56.11 | 58.56 | 60.97 | 62.64 | 63.70 | 64.05 | 61.70 | 56.16 | 51.58 | 57.90 | |||||||||||||
S.D. | 2.43 | 2.38 | 2.50 | 2.05 | 1.80 | 1.39 | 1.53 | 1.74 | 2.00 | 2.03 | 2.16 | 2.21 | 1.25 | |||||||||||||
SKEW | 0.28 | 0.17 | 0.04 | -0.09 | 0.30 | -0.44 | 0.50 | 0.57 | 0.86 | 0.23 | 0.05 | -0.17 | 0.71 | |||||||||||||
MAX | 57.95 | 58.40 | 59.71 | 61.18 | 63.21 | 63.53 | 66.45 | 68.29 | 70.07 | 66.31 | 61.72 | 56.34 | 60.49 | |||||||||||||
MIN | 47.52 | 48.66 | 50.46 | 50.43 | 55.16 | 57.67 | 59.03 | 60.52 | 60.55 | 57.37 | 51.55 | 46.81 | 56.14 | |||||||||||||
YRS | 56 | 58 | 57 | 58 | 57 | 53 | 54 | 56 | 60 | 58 | 59 | 57 | 34 |