| Year | May | June | |||
| 20 | 30 | 10 | 20 | 30 | |
| 1987 | 0 | 20 | 88 | 99 | 100 |
| 1988 | 0 | 14 | 81 | 96 | 100 |
| 1989 | 0 | 4 | 54 | 87 | 99 |
| 1990 | 0 | 4 | 40 | 81 | 98 |
| 1991 | 0 | 16 | 78 | 99 | 100 |
| 1992 | 0 | 3 | 29 | 89 | 98 |
| 1993 | 0 | 11 | 77 | 98 | |
| 1994 | 0 | 24 | 79 | 100 | |
| 1995 | 0 | 4 | 55 | 87 | 99 |
| 1996 | 0 | 11 | 53 | 89 | |
| Year | June | July | |||
| 10 | 20 | 30 | 10 | 20 | |
| 1987 | 9 | 53 | 88 | 100 | |
| 1988 | 1 | 19 | 84 | 99 | 100 |
| 1989 | 0 | 3 | 41 | 88 | 98 |
| 1990 | 0 | 2 | 33 | 84 | 96 |
| 1991 | 2 | 41 | 86 | 98 | 100 |
| 1992 | 0 | 2 | 24 | 60 | 80 |
| 1993 | 0 | 12 | 60 | 85 | |
| 1994 | 0 | 2 | 37 | 85 | 97 |
| 1995 | 0 | 7 | 29 | 89 | 97 |
| 1996 | 0 | 30 | 73 | 91 | |
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| Illinois Agricultural Statistics Service Annual Summary - 1997 |
Page 65 |
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