The method for calculating Smolt-to-Adult Ratio (SAR) estimates for CWT is based on:
Skalski J.R., and R.L. Townsend. 2005. Pacific Northwest Hatcheries Smolt-to-Adult Ratio (SAR) Estimation using Coded Wire Tags (CWT) Data. Technical Report to Bonneville Power Administration, Project No. 1991-051-00, Contract No. 00013690.
 )
: Estimate of the total CWTs recovered for a release 
group, taking into account the subsampling process of examining fish 
for tags.
)
: Estimate of the total CWTs recovered for a release 
group, taking into account the subsampling process of examining fish 
for tags.
 / R (number released). Release size weighted SAR presented for Brood Year; Equation 10 from Skalski and Townsend, 2005. Standard error calculated from SAR varianced weighted by release size, Equation 11.
 / R (number released). Release size weighted SAR presented for Brood Year; Equation 10 from Skalski and Townsend, 2005. Standard error calculated from SAR varianced weighted by release size, Equation 11.