YEAR(S) | JAN | FEB | MAR | APR | MAY | JUN | JUL | AUG | SEP | OCT | NOV | DEC | ANN | |||||||||||||
1961 | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | 68.27 | 60.42 | 64.34 | j | ||
1962 | 61.13 | 63.54 | 64.87 | 84.83 | 86.32 | 96.80 | 101.74 | 103.20 | a | 94.43 | 85.23 | 75.93 | 66.84 | 82.07 | ||||||||||||
1963 | 60.58 | 71.29 | 70.45 | 77.13 | 91.14 | b | 93.67 | 102.19 | 95.97 | 96.43 | 87.19 | 70.77 | 66.84 | 81.97 | ||||||||||||
1964 | 60.30 | a | 62.31 | 67.19 | 76.60 | 87.43 | a | 95.90 | 101.60 | a | 95.77 | 90.97 | a | 88.27 | a | 67.37 | 62.24 | b | 79.66 | |||||||
1965 | 64.23 | 64.52 | a | 66.48 | 75.10 | 85.00 | a | 92.18 | b | 101.33 | a | 100.94 | 91.40 | 88.94 | 73.43 | 62.10 | 80.47 | |||||||||
1966 | 59.23 | 60.14 | 74.13 | a | 82.43 | 92.19 | 98.80 | 101.87 | 100.10 | a | 93.07 | 84.26 | 74.30 | 64.45 | 82.08 | |||||||||||
1967 | 66.27 | a | 70.25 | 75.29 | 73.60 | 88.06 | 93.83 | 101.32 | 99.19 | 96.57 | 88.00 | 76.73 | 57.23 | 82.20 | ||||||||||||
1968 | 58.29 | 70.21 | 72.20 | a | 79.03 | 91.87 | 102.25 | b | 101.29 | ----- | z | ----- | z | ----- | z | 72.33 | f | 62.12 | e | 79.66 | d | |||||
1969 | 64.21 | b | 63.18 | f | 67.43 | c | 81.60 | 91.23 | 95.93 | 102.77 | 104.16 | 96.53 | 81.81 | 71.39 | b | 64.34 | b | 83.76 | a | |||||||
1970 | 63.90 | b | 70.71 | 67.48 | 75.13 | 91.48 | 99.50 | 103.68 | 100.59 | b | 91.11 | b | 80.13 | a | 73.72 | a | 63.87 | a | 81.78 | |||||||
1971 | 65.52 | b | 66.68 | 75.55 | b | 80.00 | e | 84.61 | c | 97.53 | 103.77 | 96.32 | 94.80 | 78.45 | 71.00 | 60.32 | 81.21 | |||||||||
1972 | 65.90 | 71.24 | d | 82.07 | b | 82.17 | a | 89.07 | c | 97.48 | a | 103.62 | b | 98.10 | a | 93.88 | d | 77.30 | a | 65.39 | b | 59.28 | b | 82.13 | ||
1973 | 59.31 | b | 63.92 | b | 61.41 | d | 76.00 | e | 91.23 | e | 98.96 | b | 102.00 | b | 100.74 | 95.21 | a | 88.04 | g | 70.79 | b | 66.85 | d | 80.58 | a | |
1974 | 61.87 | h | 67.52 | e | 74.24 | f | ----- | z | 93.29 | 103.29 | b | 100.17 | b | 99.14 | c | 94.33 | 84.48 | b | 68.42 | d | 59.90 | b | 85.62 | c | ||
1975 | 64.64 | c | 64.76 | c | 75.50 | y | 75.44 | e | 90.55 | 99.77 | 103.67 | m | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | 79.03 | g | ||
1976 | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z |
1977 | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z |
1978 | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z |
1979 | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z |
1980 | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z |
1981 | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z |
1982 | ----- | z | ----- | z | 67.46 | c | 79.37 | c | 87.85 | e | 95.68 | e | 99.70 | a | 99.67 | g | 93.40 | e | 83.69 | b | 68.11 | c | 61.96 | e | 81.91 | c |
1983 | 64.57 | a | 62.70 | a | 66.32 | 74.15 | c | 89.34 | b | 96.40 | 102.45 | b | 100.16 | f | 97.93 | c | 82.10 | a | 69.34 | a | 63.26 | d | 78.96 | a | ||
1984 | 66.24 | b | 68.56 | b | 74.40 | k | 77.92 | e | 94.40 | a | 96.40 | e | 99.26 | h | 97.50 | c | 93.92 | f | 76.41 | n | 72.00 | p | 56.00 | y | 83.50 | f |
1985 | 61.93 | p | 60.92 | o | 70.22 | h | 82.36 | h | 88.89 | d | 100.30 | g | 102.52 | f | 100.08 | f | 87.96 | g | 81.35 | e | 67.41 | c | 65.29 | c | 75.73 | h |
1986 | 71.41 | b | 64.40 | m | 73.71 | j | 82.31 | a | 89.07 | b | 99.76 | e | 98.36 | c | 100.11 | c | 88.00 | a | 80.97 | b | 72.07 | 63.41 | d | 84.55 | b | |
1987 | 62.21 | b | 64.52 | a | 69.48 | b | 85.33 | 88.71 | 100.41 | a | 100.90 | a | 99.26 | 94.40 | 86.94 | 68.43 | 59.64 | c | 81.69 | |||||||
1988 | 61.17 | b | 69.34 | 74.39 | 79.00 | 89.97 | 100.57 | 102.16 | 98.87 | 94.07 | 88.35 | 70.93 | a | 62.23 | a | 82.59 | ||||||||||
1989 | 62.06 | 67.86 | 78.45 | 88.43 | 91.26 | 98.80 | 104.48 | 99.03 | 96.47 | 83.53 | a | 74.59 | a | 64.77 | 84.15 | |||||||||||
1990 | 62.70 | a | 63.64 | 72.77 | a | 81.67 | 87.27 | a | 102.13 | 99.42 | 96.52 | 93.24 | a | 85.84 | 74.45 | a | 60.13 | 81.65 | ||||||||
1991 | 62.06 | 73.07 | 64.73 | a | 78.70 | 87.16 | 95.07 | a | 101.26 | 100.68 | 94.50 | 87.28 | b | 71.10 | a | 62.19 | 81.48 | |||||||||
1992 | 62.58 | 66.31 | 68.68 | 83.30 | 88.97 | 96.97 | 100.65 | 98.03 | 95.83 | a | 86.00 | 68.48 | a | 59.27 | a | 81.25 | ||||||||||
1993 | 60.67 | a | 61.64 | 71.71 | 80.87 | 91.61 | 98.37 | 99.58 | 99.03 | 95.73 | 82.17 | b | 68.07 | b | 65.70 | d | 81.26 | |||||||||
1994 | 67.03 | b | 64.61 | 74.71 | 81.70 | 87.84 | 102.93 | 102.71 | 103.42 | 96.33 | 81.07 | a | 67.41 | a | 63.48 | b | 82.77 | |||||||||
1995 | 60.23 | a | 70.41 | a | 71.35 | 76.83 | 83.84 | 96.53 | 104.00 | a | 103.61 | 96.77 | 86.97 | a | 75.73 | 65.53 | a | 82.65 | ||||||||
1996 | 65.84 | 69.59 | 73.84 | 83.07 | 92.03 | a | 101.07 | b | 102.77 | e | 100.28 | f | 89.76 | e | 84.39 | h | 73.83 | f | 65.42 | g | 84.75 | d | ||||
1997 | 61.58 | g | 66.79 | i | 78.52 | b | 77.44 | c | 95.11 | d | 96.00 | e | 102.24 | f | 101.36 | c | 97.11 | c | 82.71 | g | 71.96 | f | 60.45 | i | 90.92 | f |
1998 | 62.62 | e | 57.91 | e | 68.08 | f | 74.86 | i | 84.15 | e | 94.92 | e | 102.27 | i | 101.71 | c | 96.21 | f | 82.46 | g | 72.19 | d | 63.67 | g | 78.92 | f |
1999 | 67.12 | g | 69.80 | c | 73.83 | h | 74.67 | l | 87.26 | d | 97.37 | c | 98.26 | d | 100.31 | b | 95.11 | b | 90.30 | d | 80.50 | h | 63.62 | g | 91.20 | e |
2000 | 67.14 | b | 70.13 | f | 72.08 | g | 85.14 | h | 93.88 | g | 99.46 | d | 102.29 | c | 100.54 | g | 98.12 | d | 79.00 | h | 62.50 | b | 66.04 | h | 85.90 | g |
2001 | 60.20 | f | 64.00 | h | 72.71 | c | 81.19 | i | 96.96 | e | 101.38 | f | 101.04 | g | 100.52 | d | 98.67 | f | 86.04 | d | 74.04 | c | 61.12 | f | 86.05 | g |
2002 | 62.57 | h | 70.79 | d | 75.22 | h | 85.33 | f | 92.04 | e | 102.11 | c | 103.04 | c | 101.29 | c | 96.46 | f | 81.00 | e | 73.56 | e | 61.68 | i | 89.12 | e |
2003 | 71.12 | f | 63.56 | c | 70.54 | e | 79.13 | g | 93.58 | g | 100.58 | d | 104.36 | f | 102.05 | k | 98.79 | f | 90.96 | f | 68.65 | g | 64.60 | f | 78.23 | i |
2004 | 62.85 | d | 65.16 | d | 82.14 | i | 80.38 | d | 92.29 | c | 100.79 | b | 103.08 | f | 100.25 | c | 96.96 | e | 82.36 | c | 65.52 | e | 62.74 | l | 82.95 | c |
2005 | 64.04 | f | 63.92 | c | 70.43 | a | 82.62 | f | 92.85 | e | 100.50 | d | 106.29 | g | 100.18 | c | 97.79 | a | 85.75 | c | 75.26 | c | 64.97 | b | 83.52 | c |
2006 | 67.44 | d | 71.85 | a | 70.46 | c | 83.32 | e | 96.61 | c | 104.39 | b | 105.71 | c | 100.84 | 93.86 | b | 83.48 | b | 75.86 | b | 61.29 | g | 86.71 | a | |
2007 | 59.76 | f | 67.28 | c | 78.55 | b | 82.52 | c | 94.92 | e | 101.93 | a | 102.96 | c | 103.79 | b | 97.57 | b | 87.10 | b | 79.33 | c | 59.07 | c | 86.82 | a |
2008 | 59.21 | b | 65.22 | b | 75.00 | c | 83.54 | d | 89.54 | g | 103.43 | b | 103.79 | b | 102.50 | c | 97.76 | a | 87.42 | e | 74.77 | 61.45 | 83.10 | a | ||
2009 | 67.68 | c | 68.41 | a | 75.94 | 81.29 | b | 94.52 | 96.07 | a | 105.62 | b | 103.55 | b | 98.17 | 81.96 | d | 75.85 | c | 59.56 | d | 84.05 | ||||
2010 | 62.74 | d | 64.08 | b | 69.60 | f | 77.22 | c | 85.92 | f | 100.42 | d | 104.13 | h | 101.89 | d | 100.43 | b | 83.52 | d | 70.18 | b | 68.68 | i | 82.56 | d |
2011 | 65.34 | b | 64.30 | e | 77.55 | b | 81.25 | f | 89.09 | h | 100.75 | b | 104.56 | f | 106.43 | h | 100.45 | h | 90.19 | j | 73.22 | g | 61.74 | h | 76.99 | h |
2012 | 67.23 | i | 69.05 | h | 75.62 | e | 85.33 | i | 94.61 | h | 102.67 | i | 102.72 | f | 104.15 | k | 96.82 | h | 89.18 | i | 79.38 | f | 62.77 | i | 75.62 | k |
2013 | 63.40 | f | 64.92 | b | 78.88 | e | 83.67 | f | 92.64 | i | 104.58 | f | 102.62 | j | 103.74 | d | 96.22 | c | 83.09 | h | 75.39 | g | 66.87 | h | 85.94 | h |
2014 | 69.91 | h | 72.70 | a | 77.38 | e | 84.74 | g | 91.52 | j | 101.77 | d | 104.37 | d | 98.20 | f | 96.81 | d | 88.20 | a | 74.48 | a | 64.17 | b | 84.99 | d |
2015 | 66.00 | y | 73.12 | c | 79.79 | b | 82.31 | d | 86.77 | a | 102.93 | b | 101.86 | c | 106.17 | a | 98.90 | a | 86.26 | 70.59 | c | 62.10 | a | 86.44 | a | |
2016 | 62.34 | b | 76.52 | 79.69 | b | 83.07 | a | 88.90 | b | 105.34 | a | 105.67 | a | 101.03 | b | 95.55 | a | 90.30 | a | 75.24 | a | 66.21 | c | 85.82 | ||
2017 | 60.69 | b | 69.62 | b | 80.77 | a | 84.36 | e | 92.41 | b | 105.50 | 104.07 | b | 103.68 | 96.57 | b | 91.56 | f | 80.37 | c | 71.08 | f | 87.80 | b | ||
2018 | 70.64 | c | 68.07 | 75.47 | a | 87.28 | a | 92.72 | b | 102.53 | 105.86 | c | 102.10 | a | 100.11 | c | 79.40 | a | 72.04 | c | 64.32 | c | 85.05 | |||
2019 | 64.52 | b | 60.88 | b | 72.93 | b | 83.46 | b | 84.24 | b | 99.36 | b | 105.43 | a | 106.24 | b | 94.81 | c | 84.77 | 74.21 | b | 62.79 | b | 82.81 | ||
2020 | 65.61 | c | 66.72 | d | 70.21 | c | 82.97 | a | 96.42 | e | 101.45 | a | 107.04 | c | 108.46 | c | 100.00 | d | 92.20 | a | 79.31 | d | 65.70 | a | 86.34 | |
2021 | 65.36 | f | 68.74 | a | 73.50 | c | 85.57 | b | 92.83 | b | 104.64 | e | 101.36 | c | 101.25 | c | 97.30 | c | 83.67 | a | 80.38 | d | 69.15 | d | 87.13 | a |
2022 | 67.75 | k | 69.12 | b | 77.73 | a | 86.12 | e | 94.66 | b | 104.79 | a | 105.48 | b | 101.38 | b | 98.90 | a | 84.33 | a | 68.90 | a | 62.56 | d | 86.72 | a |
2023 | 60.76 | b | 64.62 | b | 68.14 | b | 83.56 | c | 91.67 | d | 97.83 | 110.28 | b | 106.10 | b | 98.57 | g | 89.58 | 76.50 | h | 68.83 | b | 84.14 | b | ||
2024 | 61.24 | b | 67.03 | 71.29 | 80.81 | n | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | ----- | z | 66.52 | i | ||
Period of Record Statistics | ||||||||||||||||||||||||||
MEAN | 63.49 | 67.01 | 72.82 | 80.84 | 90.40 | 99.46 | 102.76 | 101.08 | 95.63 | 84.84 | 72.14 | 63.11 | 82.48 | |||||||||||||
S.D. | 3.07 | 3.83 | 4.81 | 3.68 | 3.41 | 3.26 | 2.38 | 2.81 | 2.68 | 3.42 | 4.08 | 2.80 | 1.63 | |||||||||||||
SKEW | 0.54 | 0.04 | -0.16 | -0.17 | -0.08 | -0.07 | 0.59 | 0.31 | -0.64 | -0.09 | 0.03 | 0.10 | 0.87 | |||||||||||||
MAX | 71.41 | 76.52 | 82.07 | 88.43 | 96.96 | 105.50 | 110.28 | 108.46 | 100.43 | 92.20 | 80.38 | 69.15 | 86.34 | |||||||||||||
MIN | 58.29 | 57.91 | 61.41 | 73.60 | 83.84 | 92.18 | 98.26 | 95.77 | 88.00 | 77.30 | 62.50 | 57.23 | 79.66 | |||||||||||||
YRS | 41 | 49 | 46 | 43 | 48 | 52 | 43 | 45 | 45 | 43 | 46 | 40 | 23 |