accumulate auxillary values

[ebr567]

Hello, I have animals that die at several points during the year. At a certain time each year, I need to sum up these deaths from over the previous 365 days in order to estimate how many animals are required to replace them. How do you suggest that I find this number? I am not using the death total as a Level per se, and directly feeding it into the replacements via a flow (as I might not have enough animals ready), but I am using it as a target number to inform the real number of replacements I should try to produce.
Thank you.

[Administrator]

You accumulate them using a level, then reset the level at the end of the year (or at some other point such as when the animals are replaced).

[tomfid]

You can use a stock to keep track of this. Make the inflow the current death rate, and the outflow equal to a DELAY FIXED of the same rate, with a time constant of one year (in whatever units your model is using).

[ebr567]

Thank you, producing a level with a delayed outflow worked great.

[tomfid]

What you choose depends on what you need to represent - if you're modeling an accounting process explicitly, the pulsed or delayed reporting stock is good. If you're just capturing the natural delay and smoothing in a perception process, it's much simpler to use a SMOOTH or SMOOTH3 function.

Reporting.mdl

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