| Year | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 2022 | 317.70 | 317.70 | 320.20 | 323.50 | 334.60 | 337.10 | 340 | 343.20 | ||||
| 2021 | 294.60 | 296 | 296.90 | 301.10 | 301.90 | 304 | 305.50 | 307.40 | 308.60 | 312 | 314.30 | 317.70 |
| 2020 | 290.60 | 292 | 292.60 | 292.60 | 292.20 | 292.70 | 294.20 | 293.30 | 294.30 | 294.30 | 293.50 | 295.40 |
| 2019 | 283 | 285 | 285.10 | 288.20 | 289.20 | 289.60 | 289.50 | 291.70 | 291 | 290.40 | 291 | 291.90 |
| 2018 | 276 | 278.10 | 278.30 | 279.70 | 280.70 | 281.50 | 281.70 | 284.20 | 284.10 | 284.50 | 284.60 | 285.60 |
| 2017 | 265.50 | 268.40 | 269.30 | 270.60 | 271.70 | 272.30 | 272.90 | 274.70 | 275.10 | 275.30 | 275.80 | 278.10 |
| 2016 | 258.80 | 260 | 261.10 | 261.40 | 262.10 | 263.10 | 263.40 | 264.40 | 264.90 | 264.80 | 265.50 | 267.10 |
| 2015 | 255.40 | 256.70 | 257.10 | 258 | 258.50 | 258.90 | 258.60 | 259.80 | 259.60 | 259.50 | 259.80 | 260.60 |
| 2014 | 252.60 | 254.20 | 254.80 | 255.70 | 255.90 | 256.30 | 256 | 257 | 257.60 | 257.70 | 257.10 | 257.50 |
| 2013 | 245.80 | 247.60 | 248.70 | 249.50 | 250 | 249.70 | 249.70 | 251 | 251.90 | 251.90 | 252.10 | 253.40 |
| 2012 | 238 | 239.90 | 240.80 | 242.50 | 242.40 | 241.80 | 242.10 | 243 | 244.20 | 245.60 | 245.60 | 246.80 |
| 2011 | 229 | 231.30 | 232.50 | 234.40 | 235.20 | 235.20 | 234.70 | 236.10 | 237.90 | 238 | 238.50 | 239.40 |
| 2010 | 217.90 | 219.20 | 220.70 | 222.80 | 223.60 | 224.10 | 223.60 | 224.50 | 225.30 | 225.80 | 226.80 | 228.40 |
| 2009 | 210.10 | 211.40 | 211.30 | 211.50 | 212.80 | 213.40 | 213.40 | 214.40 | 215.30 | 216 | 216.60 | 218 |
| 2008 | 209.80 | 211.40 | 212.10 | 214 | 215.10 | 216.80 | 216.50 | 217.20 | 218.40 | 217.70 | 216 | 212.90 |
| 2007 | 201.60 | 203.10 | 204.40 | 205.40 | 206.20 | 207.30 | 206.10 | 207.30 | 208 | 208.90 | 209.70 | 210.90 |
| 2006 | 193.40 | 194.20 | 195 | 196.50 | 197.70 | 198.50 | 198.50 | 199.20 | 200.10 | 200.40 | 201.10 | 202.70 |
| 2005 | 188.90 | 189.60 | 190.50 | 191.60 | 192 | 192.20 | 192.20 | 192.60 | 193.10 | 193.30 | 193.60 | 194.10 |
| 2004 | 183.10 | 183.80 | 184.60 | 185.70 | 186.50 | 186.80 | 186.80 | 187.40 | 188.10 | 188.60 | 189 | 189.90 |
| 2003 | 178.40 | 179.30 | 179.90 | 181.20 | 181.50 | 181.30 | 181.30 | 181.60 | 182.50 | 182.60 | 182.70 | 183.50 |
| 2002 | 173.30 | 173.80 | 174.50 | 175.70 | 176.20 | 176.20 | 175.90 | 176.40 | 177.60 | 177.90 | 178.20 | 178.50 |
| 2001 | 171.10 | 172 | 172.20 | 173.10 | 174.20 | 174.40 | 173.30 | 174 | 174.60 | 174.30 | 173.60 | 173.40 |
| 2000 | 166.60 | 167.50 | 168.40 | 170.10 | 170.70 | 171.10 | 170.50 | 170.50 | 171.70 | 171.60 | 172.10 | 172.20 |
| 1999 | 163.40 | 163.70 | 164.10 | 165.20 | 165.60 | 165.60 | 165.10 | 165.50 | 166.20 | 166.50 | 166.70 | 167.30 |
| 1998 | 159.50 | 160.30 | 160.80 | 162.60 | 163.50 | 163.40 | 163 | 163.70 | 164.40 | 164.50 | 164.40 | 164.40 |
| 1997 | 154.40 | 155 | 155.40 | 156.30 | 156.90 | 157.50 | 157.50 | 158.50 | 159.30 | 159.50 | 159.60 | 160 |
| 1996 | 150.20 | 150.90 | 151.50 | 152.60 | 152.90 | 153 | 152.40 | 153.10 | 153.80 | 153.80 | 153.90 | 154.40 |
| 1995 | 146 | 146.90 | 147.50 | 149 | 149.60 | 149.80 | 149.10 | 149.90 | 150.60 | 149.80 | 149.80 | 150.70 |
| 1994 | 141.30 | 142.10 | 142.50 | 144.20 | 144.70 | 144.70 | 144 | 144.70 | 145 | 145.20 | 145.30 | 146 |
| 1993 | 137.90 | 138.80 | 139.30 | 140.60 | 141.10 | 141 | 140.70 | 141.30 | 141.90 | 141.80 | 141.60 | 141.90 |
| 1992 | 135.60 | 136.30 | 136.70 | 138.80 | 139.30 | 139.30 | 138.80 | 138.90 | 139.40 | 139.90 | 139.70 | 139.20 |
| 1991 | 130.20 | 130.90 | 131.40 | 133.10 | 133.50 | 134.10 | 133.80 | 134.10 | 134.60 | 135.10 | 135.60 | 135.70 |
| 1990 | 119.50 | 120.20 | 121.40 | 125.10 | 126.20 | 126.70 | 126.80 | 128.10 | 129.30 | 130.30 | 130 | 129.90 |
| 1989 | 111 | 111.80 | 112.30 | 114.30 | 115 | 115.40 | 115.50 | 115.80 | 116.60 | 117.50 | 118.50 | 118.80 |
| 1988 | 103.30 | 103.70 | 104.10 | 105.80 | 106.20 | 106.60 | 106.70 | 107.90 | 108.40 | 109.50 | 110 | 110.30 |
| 1987 | 100 | 100.40 | 100.60 | 101.80 | 101.90 | 101.90 | 101.80 | 102.10 | 102.40 | 102.90 | 103.40 | 103.30 |
| (1986) | 96.20 | 96.60 | 96.70 | 97.70 | 97.80 | 97.80 | 97.50 | 97.80 | 98.30 | 98.50 | 99.30 | 99.60 |
| 1986 | 379.70 | 381.10 | 381.60 | 385.30 | 386 | 385.80 | 384.70 | 385.90 | 387.80 | 388.40 | 391.70 | 393 |
| 1985 | 359.80 | 362.70 | 366.10 | 373.90 | 375.60 | 376.40 | 375.70 | 376.70 | 376.50 | 377.10 | 378.40 | 378.90 |
| 1984 | 342.60 | 344 | 345.10 | 349.70 | 351 | 351.90 | 351.50 | 354.80 | 355.50 | 357.70 | 358.80 | 358.50 |
| 1983 | 325.90 | 327.30 | 327.90 | 332.50 | 333.90 | 334.70 | 336.50 | 338 | 339.50 | 340.70 | 341.90 | 342.80 |
| 1982 | 310.60 | 310.70 | 313.40 | 319.70 | 322 | 322.90 | 323 | 323.10 | 322.90 | 324.50 | 326.10 | 325.50 |
| 1981 | 277.30 | 279.80 | 284 | 292.20 | 294.10 | 295.80 | 297.10 | 299.30 | 301 | 303.70 | 306.90 | 308.80 |
| 1980 | 245.30 | 248.80 | 252.20 | 260.80 | 263.20 | 265.70 | 267.90 | 268.50 | 270.20 | 271.90 | 274.10 | 275.60 |
| 1979 | 207.20 | 208.90 | 210.60 | 214.20 | 215.90 | 219.60 | 229.10 | 230.90 | 233.20 | 235.60 | 237.70 | 239.40 |
| 1978 | 189.50 | 190.60 | 191.80 | 194.60 | 195.70 | 197.20 | 198.10 | 199.40 | 200.20 | 201.10 | 202.50 | 204.20 |
| 1977 | 172.40 | 174.10 | 175.80 | 180.30 | 181.70 | 183.60 | 183.80 | 184.70 | 185.70 | 186.50 | 187.40 | 188.40 |
| 1976 | 147.90 | 149.80 | 150.60 | 153.50 | 155.20 | 156 | 156.30 | 158.50 | 160.60 | 163.50 | 165.80 | 168 |
| 1975 | 119.90 | 121.90 | 124.30 | 129.10 | 134.50 | 137.10 | 138.50 | 139.30 | 140.50 | 142.50 | 144.20 | 146 |
| 1974 | 100 | 101.70 | 102.60 | 106.10 | 107.60 | 108.70 | 109.70 | 109.80 | 111 | 113.20 | 115.20 | 116.90 |
| 1973 | 89.30 | 89.80 | 90.40 | 92.10 | 92.80 | 93.20 | 93.60 | 94.70 | 96.60 | 97.30 | 97.30 | 98.10 |
| 1972 | 82.90 | 83.30 | 83.50 | 84.30 | 84.70 | 85.30 | 85.60 | 85.20 | 86.70 | 87.90 | 88.20 | 88.70 |
| 1971 | 76.60 | 77.10 | 77.70 | 79.30 | 79.80 | 80.50 | 80.90 | 80.90 | 81 | 81.50 | 82 | 82.40 |
| 1970 | 70.60 | 71 | 71.40 | 72.50 | 72.70 | 72.90 | 73.50 | 73.40 | 73.70 | 74.60 | 75.10 | 75.60 |