Variable In A Date Calculation

I have the following date calculation :
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Private Sub StatofLimits_GotFocus()
'--Determines Statute of Limitations accounting for minors.
If DateAdd("yyyy", 18, Me.Txt14) > Me.txtBegin Then
Me.StatofLimits = DateAdd("yyyy", 20, Me.Txt14)
Else
Me.StatofLimits = DateAdd("yyyy", 2, Me.txtBegin)
End If
End Sub
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Here is my problem. The number "2" in the else statement (Me.StatofLimits = DateAdd("yyyy", 2, Me.txtBegin)in the above example is a variable. The variable is selected from a combobox and stored in an unbound textbox. The variable will always represent a number of years-ie 3 years, 4 years, etc. I need to modify my calculation so that it will pull the variable from my textbox:
I know this isn't correct but this is what I need:

Me.StatofLimits = DateAdd("yyyy", (Number from MyTxtBox), Me.txtBegin)



Can anyone give me the correct syntext?

Pat, If you read this, I did listen. The reason I need to modify my calculation and use a variable is because I moved my Statute of Limitation Dates to the same table and different case types have different Statutes. They can be anywhere from 2 to 6 years.