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Example of SP calculation based on the rate of change between population counts
| Year | 1 | 2 | 3 | 4 | 5 | 6 |
|---|---|---|---|---|---|---|
| Population count | 50 | 60 | 75 | 70 | 60 | 45 |
| Change | NA | 10 | 15 | −5 | −10 | −15 |
| Rate of change | NA | NA | 5 | −20 | −5 | −5 |
| SP presence | NA | NA | 0 | 1 | 0 | 0 |
Change in population count was calculated by taking the yearly difference between counts, rate of change was calculated by taking the difference in change in counts and SPs were identified when the rate of changed switched from positive to negative.
