Salmon/Steelhead Returns based on PIT tags?

[Biigfish33]

Wanted to see if anyone knows if there is data readily available to the public about PIT tag detection ratios. I.e. how many fish per 1 pit tag detection are expected to return to a given release site? I know these ratios exist to estimate hatchery returns, etc. but I haven’t been able to find anything online spelling out expected returns based on pit tag detections. I’ve been looking into some of the small detection sites on the main salmon and have seen a few fish trickling by the last month or so, but curious about what the total number of fish moving up may be based on the 1-2 detections I saw.
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