YEAR(S) | JAN | FEB | MAR | APR | MAY | JUN | JUL | AUG | SEP | OCT | NOV | DEC | ANN | |||||||||||||
1959 | ----- | z | 65.00 | k | 73.68 | 82.10 | 84.94 | 96.67 | 95.52 | 87.97 | 90.77 | 82.90 | 70.70 | 62.29 | 82.75 | b | ||||||||||
1960 | 58.52 | 60.83 | 75.52 | 79.77 | 85.81 | 98.30 | 96.61 | 92.10 | 92.70 | 78.90 | 72.97 | 63.87 | a | 79.66 | ||||||||||||
1961 | 64.65 | 68.21 | 71.55 | 81.20 | 86.32 | 96.47 | 94.32 | 90.37 | a | 86.97 | 81.74 | 67.13 | 60.65 | 79.13 | ||||||||||||
1962 | 60.97 | 66.39 | 64.61 | 83.43 | 84.13 | 93.47 | 95.03 | 97.52 | 89.43 | 82.39 | 72.90 | 63.77 | 79.50 | |||||||||||||
1963 | 59.97 | 69.64 | 70.16 | 76.47 | 88.52 | 91.07 | 96.52 | 89.35 | 91.17 | 84.77 | 70.21 | a | 66.03 | 79.49 | ||||||||||||
1964 | 61.77 | 61.72 | 65.52 | 73.97 | 85.23 | 92.57 | 96.43 | a | 89.58 | 85.77 | 84.29 | 68.00 | 64.77 | 77.47 | ||||||||||||
1965 | 66.84 | 64.54 | b | 67.69 | b | 77.36 | b | 83.10 | b | 89.17 | 94.80 | a | 93.42 | 88.10 | 87.23 | a | 73.46 | b | 61.11 | d | 78.90 | |||||
1966 | 60.10 | 59.54 | 72.81 | 78.30 | 87.52 | b | 94.23 | 95.29 | 89.55 | 87.63 | 82.06 | 74.47 | 64.26 | 78.81 | ||||||||||||
1967 | 67.00 | 69.71 | 74.77 | 74.57 | 85.23 | a | 91.17 | 93.81 | 92.84 | 89.87 | 85.10 | 74.97 | 58.84 | 79.82 | ||||||||||||
1968 | 63.03 | 69.45 | 67.55 | 74.10 | 85.48 | 95.47 | 92.13 | 88.97 | 90.47 | 84.65 | 70.03 | 63.84 | 78.76 | |||||||||||||
1969 | 65.81 | 63.04 | 67.23 | 79.37 | 86.48 | 91.63 | 94.45 | 94.06 | 90.67 | 79.00 | 69.57 | 65.03 | 78.86 | |||||||||||||
1970 | 64.23 | 69.21 | 66.55 | 74.17 | 87.84 | 95.13 | 96.74 | 92.61 | 86.40 | 78.19 | 74.20 | 65.16 | 79.20 | |||||||||||||
1971 | 66.58 | 65.11 | 74.94 | 76.70 | 81.45 | 92.43 | 96.42 | 87.23 | 89.47 | 74.71 | 69.40 | 58.48 | 77.74 | |||||||||||||
1972 | 65.81 | 70.28 | 79.19 | 81.07 | 84.26 | 92.77 | 97.35 | 91.90 | a | 89.77 | 77.87 | a | 65.23 | 61.47 | a | 79.75 | ||||||||||
1973 | 59.71 | 63.32 | 61.30 | a | 72.57 | 86.35 | 94.63 | 94.81 | 94.39 | 92.33 | 84.31 | b | 71.67 | 67.16 | 78.55 | |||||||||||
1974 | 62.58 | 67.61 | 71.71 | 78.80 | 86.39 | 98.60 | 92.68 | 92.35 | 87.77 | 78.65 | 69.97 | 60.45 | 78.96 | |||||||||||||
1975 | 64.35 | 65.11 | 67.58 | 70.50 | 82.68 | 92.77 | ----- | z | 95.44 | d | 88.73 | d | 81.57 | c | 72.96 | d | 64.69 | b | 76.94 | a | ||||||
1976 | 65.97 | 67.81 | b | 70.62 | b | 75.61 | g | 85.30 | a | 94.11 | b | 90.37 | a | 94.67 | d | 86.79 | b | 78.10 | 71.69 | a | 64.05 | i | 80.54 | b | ||
1977 | 60.54 | e | 69.68 | c | 67.00 | e | 81.06 | m | 80.32 | f | 95.66 | a | 94.40 | a | 93.37 | a | 91.12 | e | ----- | z | ----- | z | 67.48 | b | 79.91 | d |
1978 | 63.25 | c | 61.81 | a | 69.52 | b | 75.81 | c | 84.18 | c | 97.40 | 95.59 | b | 93.79 | b | 89.14 | a | 85.11 | d | 66.03 | 57.12 | e | 78.23 | |||
1979 | 55.23 | i | ----- | z | 64.61 | 77.76 | e | ----- | z | 93.60 | e | 98.81 | e | ----- | z | 95.53 | 89.97 | ----- | z | ----- | z | 86.71 | f | |||
1980 | ----- | z | 68.43 | a | 67.92 | e | 77.04 | g | 82.68 | i | 98.56 | e | 97.77 | a | 94.21 | g | 92.60 | 82.73 | a | 70.50 | h | 70.95 | j | 84.67 | f | |
1981 | 64.97 | 70.92 | d | 66.82 | c | 81.52 | c | 82.37 | a | 97.87 | 94.45 | 96.23 | e | 90.93 | c | 78.97 | 75.93 | 70.58 | 80.96 | |||||||
1982 | 63.86 | c | 66.78 | e | 69.59 | b | 79.87 | 85.31 | b | 92.70 | 93.90 | 93.10 | 91.25 | b | 83.00 | a | 67.90 | a | 59.90 | a | 78.93 | |||||
1983 | 64.21 | c | 64.39 | 66.63 | d | 71.31 | a | 84.69 | b | 91.93 | a | 96.03 | b | 89.68 | 89.79 | a | 76.83 | g | 68.50 | b | 66.45 | 77.60 | a | |||
1984 | 63.58 | 69.29 | a | 73.94 | 77.25 | f | 92.14 | b | 92.04 | d | 89.93 | a | 88.13 | 89.45 | a | 76.45 | 71.23 | 61.87 | a | 78.91 | a | |||||
1985 | 59.48 | 65.68 | 71.62 | r | 81.56 | c | 85.84 | f | 99.16 | e | 96.03 | a | 93.74 | 85.67 | 81.00 | d | 67.90 | 68.81 | 79.90 | b | ||||||
1986 | 72.81 | 69.32 | 73.32 | 78.70 | 86.58 | 94.57 | 91.16 | 90.55 | 85.67 | 78.87 | 70.13 | 62.71 | 79.53 | |||||||||||||
1987 | 62.20 | a | 62.37 | a | 66.77 | 79.43 | 80.74 | 94.50 | 94.23 | 89.29 | 87.00 | 84.00 | 68.03 | 60.35 | 77.41 | |||||||||||
1988 | 62.48 | 67.52 | 71.26 | 76.03 | 84.35 | 95.07 | 92.61 | 89.70 | a | 88.77 | 84.16 | 71.03 | 62.35 | 78.78 | ||||||||||||
1989 | 60.06 | ----- | z | 73.20 | u | 85.00 | 87.32 | 95.47 | 96.03 | 89.45 | 91.40 | 80.65 | 73.73 | 65.00 | 82.41 | b | ||||||||||
1990 | 62.53 | a | 64.56 | a | 70.29 | 77.33 | 84.73 | a | 97.93 | 88.57 | a | 87.87 | a | 87.04 | b | 81.43 | a | 71.67 | 59.24 | b | 77.77 | |||||
1991 | 60.81 | 68.46 | 62.76 | b | 74.79 | a | 83.13 | a | 90.53 | 93.39 | 92.72 | b | 85.89 | b | 83.55 | b | 69.00 | 59.20 | a | 77.02 | ||||||
1992 | 58.97 | b | 63.31 | c | 64.26 | 77.73 | d | 83.96 | f | 92.90 | 93.27 | e | 87.71 | 90.55 | a | 84.03 | b | 67.76 | a | 59.87 | 76.40 | a | ||||
1993 | 60.29 | 60.41 | a | 69.81 | 78.83 | a | 85.69 | r | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | 67.33 | h | ||
1994 | 65.77 | 62.82 | 71.17 | b | 77.50 | 83.42 | 97.30 | 97.48 | 95.27 | a | 89.90 | 80.38 | b | 65.47 | 62.97 | 79.12 | ||||||||||
1995 | 59.97 | 68.07 | 69.45 | 73.87 | 79.87 | 91.72 | a | 98.10 | 94.20 | a | 90.43 | 85.90 | 76.10 | 66.30 | d | 79.50 | ||||||||||
1996 | 67.87 | 70.54 | a | 71.58 | 85.47 | 91.26 | 98.53 | 96.94 | 95.13 | 86.07 | a | 84.96 | c | 73.90 | 71.29 | c | 82.79 | |||||||||
1997 | ----- | z | 79.79 | n | 79.48 | b | 77.96 | c | 90.74 | 93.31 | d | 96.89 | c | 95.11 | l | 88.50 | f | 80.24 | b | 83.80 | t | 56.36 | c | 82.14 | e | |
1998 | 65.62 | g | 57.58 | d | 65.17 | b | 69.58 | f | 81.79 | g | 92.46 | b | 95.79 | b | 90.85 | d | 90.24 | e | 81.32 | i | 73.45 | h | 63.04 | h | 82.02 | f |
1999 | 67.90 | b | 72.73 | f | 72.85 | d | 71.83 | f | 83.43 | j | 91.95 | i | 90.23 | i | 92.18 | i | 92.04 | f | 89.43 | j | 79.76 | e | 65.54 | g | 73.50 | i |
2000 | 67.52 | j | 69.52 | d | 68.81 | e | 82.36 | b | 92.22 | d | 92.89 | b | 93.96 | e | 89.81 | d | 92.83 | g | 77.04 | e | ----- | z | 70.18 | i | 83.33 | d |
2001 | 59.27 | a | 62.48 | a | 67.61 | m | 74.57 | b | 92.15 | d | 96.12 | f | 92.63 | l | 91.44 | o | 92.85 | c | 83.35 | e | 74.54 | b | 60.64 | c | 74.98 | d |
2002 | 65.25 | c | 68.92 | b | 69.88 | e | 82.05 | i | 87.73 | a | 97.82 | b | 93.45 | b | 93.41 | d | 91.27 | d | 78.70 | a | 74.33 | 60.69 | b | 80.13 | a | |
2003 | 71.81 | e | 63.95 | h | 69.29 | c | 75.24 | e | 88.18 | c | 95.40 | 98.32 | c | 91.52 | b | 91.83 | 83.63 | a | 68.10 | a | 67.03 | a | 81.85 | a | ||
2004 | 62.93 | b | 60.31 | 76.18 | c | 74.72 | e | 87.83 | g | 95.11 | b | 92.38 | e | 92.27 | e | 90.54 | b | 79.81 | e | 65.11 | c | 63.32 | c | 77.52 | a | |
2005 | 61.58 | g | 60.39 | 66.68 | c | 78.61 | b | 87.29 | 93.83 | 97.87 | a | 91.76 | b | 94.07 | b | 84.06 | 75.60 | 68.26 | 81.67 | a | ||||||
2006 | 68.55 | 70.14 | 67.19 | 80.27 | 89.74 | 97.07 | 96.37 | a | 91.26 | 85.77 | 80.68 | ----- | z | 64.29 | 81.03 | a | ||||||||||
2007 | 58.13 | 66.89 | 75.00 | 78.33 | 86.71 | 96.87 | 94.42 | 90.77 | 88.73 | 83.65 | 76.23 | 60.55 | 79.69 | |||||||||||||
2008 | 61.55 | ----- | z | 73.68 | 80.63 | 83.61 | 98.66 | a | ----- | z | 90.77 | ----- | z | ----- | z | ----- | z | ----- | z | 81.48 | f | |||||
2009 | 68.19 | ----- | z | 74.27 | a | 77.55 | a | 89.39 | 89.70 | 97.53 | a | 94.96 | d | 91.96 | d | 79.45 | ----- | z | ----- | z | 84.78 | c | ||||
2010 | 63.39 | 62.32 | 69.32 | 76.00 | c | 85.10 | 95.67 | 97.48 | 95.67 | d | 95.21 | a | 82.30 | a | 71.97 | a | 73.87 | a | 80.69 | |||||||
2011 | 67.73 | i | 64.77 | b | 78.13 | 84.43 | 85.34 | b | 98.00 | 97.32 | 97.16 | 92.69 | a | 86.52 | 68.68 | e | 59.60 | f | 85.30 | b | ||||||
2012 | 71.00 | a | 66.96 | a | 73.34 | b | 83.37 | c | 91.61 | c | 98.97 | 92.87 | a | 94.52 | 89.48 | a | 85.45 | 79.25 | b | 64.68 | 82.62 | |||||
2013 | 62.00 | 62.89 | 77.15 | d | 81.83 | a | 89.42 | g | 100.48 | e | 94.92 | f | 95.79 | g | 92.00 | 83.19 | 77.40 | 66.55 | 78.17 | c | ||||||
2014 | 72.00 | 74.36 | 75.39 | 82.00 | 94.81 | 99.97 | a | 96.60 | a | 92.06 | 87.97 | a | 84.20 | a | 73.67 | 64.32 | 83.11 | |||||||||
2015 | 66.30 | a | 72.93 | a | 76.32 | 80.03 | a | 81.73 | a | 98.47 | 92.29 | 95.90 | 89.86 | b | 81.10 | 71.07 | 64.10 | 80.84 | ||||||||
2016 | 64.77 | 76.72 | 77.48 | 79.57 | 84.10 | 98.90 | 100.27 | a | 92.45 | b | 88.03 | 89.70 | a | 75.80 | 67.42 | 82.93 | ||||||||||
2017 | 61.84 | 68.85 | a | 80.55 | 84.17 | 87.65 | 102.27 | 94.06 | 94.13 | 91.10 | 90.16 | 82.60 | 69.58 | 83.91 | ||||||||||||
2018 | 72.06 | 66.96 | 75.55 | 85.03 | 90.97 | 100.03 | 97.30 | a | 93.33 | a | 93.90 | 78.70 | a | 73.13 | 63.84 | 82.57 | ||||||||||
2019 | 65.06 | 60.32 | 75.00 | 81.87 | 82.68 | 96.73 | 102.13 | a | 100.16 | 91.10 | a | 85.26 | 75.07 | a | 64.93 | a | 81.69 | |||||||||
2020 | 68.03 | b | 69.07 | 69.77 | 80.93 | 94.13 | 100.53 | 102.47 | a | 101.84 | 96.80 | 93.80 | a | 79.00 | a | 66.87 | a | 85.27 | ||||||||
2021 | 66.68 | 71.25 | 74.83 | a | 85.03 | a | 90.26 | 102.63 | 94.70 | a | 93.83 | b | 91.57 | 85.03 | 81.80 | 67.77 | 83.78 | |||||||||
2022 | 67.58 | 67.82 | 74.61 | 84.23 | 91.10 | 98.60 | 96.84 | 90.77 | 91.70 | 82.03 | 68.47 | 64.06 | 81.49 | |||||||||||||
2023 | 61.55 | 61.04 | 69.48 | 81.87 | 88.13 | 96.73 | h | 105.77 | 101.10 | 96.07 | 88.35 | 75.83 | 69.39 | 81.69 | a | |||||||||||
2024 | 63.26 | 67.14 | 67.54 | c | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | 65.98 | i | ||
Period of Record Statistics | ||||||||||||||||||||||||||
MEAN | 64.15 | 66.30 | 70.99 | 78.92 | 86.59 | 95.61 | 95.58 | 92.66 | 90.13 | 82.68 | 72.20 | 64.03 | 80.09 | |||||||||||||
S.D. | 3.67 | 4.01 | 4.38 | 3.69 | 3.44 | 3.17 | 2.95 | 3.18 | 2.67 | 3.65 | 4.12 | 3.68 | 2.04 | |||||||||||||
SKEW | 0.53 | 0.01 | 0.10 | -0.14 | 0.42 | 0.08 | 0.62 | 0.70 | 0.26 | 0.46 | 0.42 | 0.23 | 0.77 | |||||||||||||
MAX | 72.81 | 76.72 | 80.55 | 85.47 | 94.81 | 102.63 | 105.77 | 101.84 | 96.80 | 93.80 | 82.60 | 73.87 | 85.27 | |||||||||||||
MIN | 58.13 | 57.58 | 61.30 | 70.50 | 79.87 | 89.17 | 88.57 | 87.23 | 85.67 | 74.71 | 65.11 | 56.36 | 77.02 | |||||||||||||
YRS | 58 | 58 | 63 | 58 | 55 | 61 | 59 | 58 | 60 | 59 | 55 | 55 | 38 |