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Table 1
Typical number of observations.
| Sampling | Set 1 | Set 2 | Set 3 | Set 4 | |
| (4050) | (4046) | (1094) | (1094) | ||
|
|
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| 1 | 2377 | 594 | 288 | 131 | |
| 4 | 735 | 187 | 96 | 25 | |
| 8 | 511 | 113 | 70 | 29 | |
| 20 | 718 | 178 | 90 | 36 | |
Notes.The number of observations takes into account the four-month gap. The numbers between parentheses indicate the time span in days for each set. The effective sampling for Set 2 should be multiplied by 3.2 (see Sect. 2.1.1).
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