Goalseek and Macros

I am trying to make an excel program that can automatically solve the AASHTO DESIGN EQUATION FOR FLEXIBLE PAVEMENT. For any civil engineers out their will attest that it is a rather large equation that can really only be directly solved using goal seek.

My plan is to be able to have the spreadsheet automatically calculate the variable I need after I enter five known values into five different cells, D11 through D15, which are all linked to the equation in another cell, G6. The unknown variable that I am solving for is in cell D16. The cell F6 is the cell value I want the equation to be equal to (generally will be 0).

I have already set up a Goalseek Macro to generate the answer and it works perfectly. However, I want the Macro to run Automatically. The Macro is as follows:

Range("G6").Goalseek Goal:=Range("f6").Value, ChangingCell:=Range("d16")

I then attempted to use the function (=IF(D15="","",Go())) In order run another Macro called Go (). This Macro is as follows

Function Go()
Go = "Goalseek"
Goalseek


End Function

The problem is I can't get the macro "Go ()" to run the Macro "Goalseek ()".


If anyone can tell me to how to make the Goalseek Macro run Automatically that would be awesome.

Thanks