FISHERY BULLETIN: VOL. 83, NO. 2 



Thus var(n:) = wariq) 





= warimtrlPtc) 



_ var(mfc) + g^ var(Ac) -2qcov{mtc,Ptc) 



Ptc' 



[aV {e«' 



'■(a^c-D + l 



1^] 



where cov {mtc, Ptc^ was estimated from the 1951-82 time series. Var (Po) was 

 computed based upon Equation (9B) 



Po = Ptce""'' 



var(Po)=-(^ 



da 



%ar(a)+^^^o 



\^Ptc 



waiiPtr ) + 2 



/dPo\ (m 



\da) \dPt, 



cov(Ac , a) 



a,^^c 



- e^a/c [^j;^2 p^^2 ^^j.^^) + var(Ac ) + 2Ac -tc -covCAe , a)] 

 where cov (Ac . «) was estimated from the 1951-82 time series. 



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