| JAN | FEB | MAR | APR | MAY | JUN | JUL | AUG | SEP | OCT | NOV | DEC | TOTALS | % CHANGE | ||
| 2008 | 57 | 62 | 53 | 172 | 0.13% | DECREASE | |||||||||
| 2007 | 51 | 67 | 79 | 56 | 80 | 61 | 91 | 57 | 71 | 60 | 63 | 71 | 807 | 20.1% | INCREASE |
| 2006 | 50 | 39 | 49 | 37 | 51 | 46 | 64 | 84 | 56 | 72 | 65 | 59 | 672 | 27.5% | INCREASE |
| 2005 | 35 | 25 | 43 | 32 | 52 | 37 | 56 | 36 | 70 | 26 | 45 | 30 | 487 | 0.0% | DECREASE |
| 2004 | 51 | 46 | 42 | 35 | 49 | 43 | 47 | 52 | 43 | 27 | 20 | 32 | 487 | 9.8% | DECREASE |
| 2003 | 26 | 42 | 33 | 34 | 39 | 39 | 66 | 35 | 53 | 71 | 44 | 58 | 540 | 19.5% | INCREASE |
| 2002 | 41 | 21 | 34 | 39 | 45 | 42 | 50 | 53 | 39 | 33 | 23 | 32 | 452 | 21.5% | INCREASE |
| 2001 | 15 | 21 | 27 | 30 | 29 | 27 | 59 | 32 | 40 | 27 | 37 | 28 | 372 | 1.6% | INCREASE |
| 2000 | 25 | 22 | 18 | 39 | 27 | 27 | 38 | 48 | 32 | 24 | 38 | 28 | 366 | 32.1% | INCREASE |
| 1999 | 28 | 22 | 21 | 21 | 25 | 17 | 20 | 30 | 26 | 22 | 24 | 21 | 277 | 11.8% | DECREASE |
| 1998 | 32 | 19 | 24 | 27 | 34 | 24 | 31 | 37 | 31 | 23 | 16 | 16 | 314 | 2.3% | INCREASE |
| 1997 | 38 | 29 | 25 | 21 | 22 | 31 | 26 | 29 | 22 | 21 | 24 | 19 | 307 | 28.1% | DECREASE |
| 1996 | 42 | 35 | 34 | 30 | 25 | 46 | 43 | 46 | 37 | 28 | 28 | 33 | 427 | 12.9% | DECREASE |
| 1995 | 25 | 33 | 43 | 31 | 51 | 43 | 68 | 43 | 44 | 39 | 36 | 34 | 490 | 60.4% | DECREASE |
| 1994 | 77 | 92 | 93 | 81 | 105 | 93 | 131 | 138 | 105 | 122 | 80 | 119 | 1,236 | 32.9% | INCREASE |
| 1993 | 65 | 59 | 76 | 90 | 70 | 81 | 93 | 71 | 83 | 89 | 84 | 69 | 930 | 8.5% | INCREASE |
| 1992 | 51 | 51 | 61 | 55 | 53 | 60 | 122 | 84 | 71 | 89 | 90 | 70 | 857 | 25.7% | INCREASE |
| 1991 | 34 | 45 | 42 | 55 | 63 | 71 | 67 | 71 | 72 | 49 | 60 | 53 | 682 | 21.6% | INCREASE |
| 1990 | 43 | 39 | 62 | 48 | 64 | 46 | 51 | 43 | 50 | 42 | 43 | 30 | 561 | 19.4% | INCREASE |
| 1989 | 35 | 40 | 43 | 37 | 31 | 44 | 42 | 43 | 44 | 40 | 28 | 43 | 470 | 7.3% | INCREASE |
| 1988 | 36 | 32 | 33 | 40 | 34 | 41 | 39 | 43 | 39 | 39 | 32 | 30 | 438 | 8.2% | DECREASE |
| 1987 | 33 | 41 | 48 | 44 | 32 | 46 | 39 | 43 | 47 | 41 | 33 | 30 | 477 | 0.2% | INCREASE |
| 1986 | 35 | 24 | 37 | 36 | 49 | 47 | 46 | 50 | 48 | 41 | 32 | 31 | 476 | 18.7% | INCREASE |
| 1985 | 27 | 22 | 21 | 27 | 38 | 29 | 49 | 38 | 36 | 45 | 38 | 31 | 401 | 9.6% | INCREASE |
| 1984 | 27 | 23 | 26 | 39 | 35 | 29 | 27 | 39 | 34 | 32 | 32 | 23 | 366 | 23.6% | DECREASE |
| 1983 | 40 | 32 | 44 | 45 | 49 | 50 | 38 | 45 | 34 | 39 | 31 | 32 | 479 | 13.4% | DECREASE |
| 1982 | 41 | 49 | 43 | 49 | 52 | 52 | 43 | 48 | 54 | 41 | 40 | 41 | 553 | 20.5% | INCREASE |
| 1981 | 48 | 28 | 36 | 35 | 30 | 33 | 39 | 53 | 38 | 45 | 35 | 39 | 459 | 4.8% | INCREASE |
| 1980 | 33 | 21 | 31 | 39 | 38 | 53 | 36 | 50 | 43 | 33 | 36 | 25 | 438 | 7.4% | DECREASE |
| 1979 | 23 | 25 | 48 | 40 | 62 | 39 | 48 | 51 | 43 | 33 | 39 | 22 | 473 | 9.0% | INCREASE |
| 1978 | 28 | 28 | 32 | 30 | 42 | 31 | 37 | 45 | 41 | 43 | 44 | 33 | 434 | 8.4% | DECREASE |
| 1977 | 12 | 30 | 37 | 38 | 47 | 49 | 39 | 56 | 64 | 42 | 33 | 27 | 474 | 48.1% | INCREASE |
| 1976 | 30 | 24 | 21 | 28 | 25 | 21 | 41 | 21 | 30 | 24 | 30 | 25 | 320 | 30.4% | DECREASE |
| 1975 | 26 | 37 | 40 | 48 | 29 | 47 | 38 | 23 | 54 | 35 | 50 | 33 | 460 | 15.6% | INCREASE |
| 1974 | 35 | 22 | 22 | 32 | 37 | 31 | 48 | 29 | 30 | 44 | 35 | 33 | 398 | 15.0% | INCREASE |
| 1973 | 16 | 21 | 27 | 26 | 40 | 28 | 17 | 36 | 37 | 38 | 30 | 30 | 346 | 0.9% | INCREASE |
| 1972 | 29 | 30 | 27 | 45 | 17 | 27 | 32 | 37 | 28 | 33 | 23 | 15 | 343 |