Table 1.
Period | No of samples examined annually | |||
Mean | SD | Range | Nr positives | |
1965 – 1973 | 68 | 54 | 4 – 159 | 101 |
1974 – 1985 | 661 | 158 | 335 – 890 | 0 |
1986 – 1989 | 2126 | 1126 | 523 – 2947 | 0 |
1: AI bulls at a station in 1970–1971
Period | No of samples examined annually | |||
Mean | SD | Range | Nr positives | |
1965 – 1973 | 68 | 54 | 4 – 159 | 101 |
1974 – 1985 | 661 | 158 | 335 – 890 | 0 |
1986 – 1989 | 2126 | 1126 | 523 – 2947 | 0 |
1: AI bulls at a station in 1970–1971