# Age-Composition Stock-Reduction Analysis

`CompSRA.Rd`

A stock reduction analysis (SRA) model is fitted to the age-composition from the last 3 years (or less if fewer data are available)

## Arguments

- x
A position in the data object

- Data
A data object

- reps
The number of stochastic samples of the MP recommendation(s)

- plot
Logical. Show the plot?

## Value

An object of class `Rec-class`

with the `TAC`

slot populated with a numeric vector of length `reps`

## Details

A stock reduction analysis (SRA) model is fitted to the age-composition
from the last 3 years (or less if fewer data are available) assuming a constant
total mortality rate (*Z*) and used to estimate current stock depletion (*D*),
\(F_\textrm{MSY}\), and stock abundance (*A*).

Abundance is estimated in the SRA. \(F_{\textrm{MSY}}\) is calculated assuming knife-edge vulnerability at the age of full selection.

The TAC is calculated as \(F_\textrm{MSY} A\). `CompSRA4010`

uses a 40-10
harvest control rule to reduce TAC at low biomass.

## Functions

`CompSRA`

: TAC is FMSY x Abundance`CompSRA4010`

: With a 40-10 control rule based on estimated depletion

## Required Data

See `Data-class`

for information on the `Data`

object

`CompSRA`

: CAA, Cat, L50, LFC, LFS, MaxAge, Mort, steep, vbK, vbLinf, vbt0, wla, wlb

`CompSRA4010`

: CAA, Cat, L50, LFC, LFS, MaxAge, Mort, steep, vbK, vbLinf, vbt0, wla, wlb

## Rendered Equations

See Online Documentation for correctly rendered equations

## Examples

```
if (FALSE) {
CompSRA(1, MSEtool::SimulatedData, plot=TRUE)
}
CompSRA4010(1, MSEtool::SimulatedData, plot=TRUE)
#> TAC (median)
#> 3944.184
```