There are a whole bunch of ways to do this depending how your database is set up. The most general approach is to have an override field that you can manually enter the tax amount into. If it's empty the tax calculates the normal way, and if it contains a value, then that value overrides the normal calculation. So, you change your tax calculation formula to:

Case(IsEmpty(TaxOverride),

...insert your original tax formula here...

,TaxOverride)

To make it look more professional, you can un-check the "allow entry into field" option from the original calculated field, and superimpose this field directly over the TaxOverride field. Make sure that you send the TaxOverride field to the back. Then, the calculated field will be what you see displayed, but when you click on it , you will actually be editing the TaxOverrid field.

The "Total" field sounds like a calc field -- and you can't edit calc fields manually, because they're calculations.

That last was just explanation of what you were experiencing; BobWeaver's solution will work.

thanks for your help, but I don't know about these formula's. This is what I have now:

Case(IsEmpty(TaxOverride),Case(T_pst_check = "X" and T_gst_check = "" ; kev total * 1.08 ; T_gst_check = "1" and T_pst_check = "" ; kev total * 1.07 ; T_gst_check = "1" and T_pst_check = "X"; (kev total * 1.15) ; kev total),TaxOverride)

and it won't accept it. Can you offer any advice?

Ok, your version of Filemaker uses semicolons for separators, not commas. So you will have to change the formula to:

Case(IsEmpty(TaxOverride);Case(T_pst_check = "X" and T_gst_check = "" ; kev total * 1.08 ; T_gst_check = "1" and T_pst_check = "" ; kev total * 1.07 ; T_gst_check = "1" and T_pst_check = "X"; (kev total * 1.15) ; kev total);TaxOverride)

or even simpler:

Case(not IsEmpty(TaxOverride); TaxOverride;

T_pst_check = "X" and T_gst_check = "" ; kev total * 1.08 ;

T_gst_check = "1" and T_pst_check = "" ; kev total * 1.07 ;

T_gst_check = "1" and T_pst_check = "X"; (kev total * 1.15);

kev total)

We have a database which we use to invoice clients. We can check a box to add tax, and then we get the total at the bottom of the page. However, some things have to have tax added and some don't - often within the same invoice. What I need is for Filemaker to do what it does now, but when we need to change the final tax-included total, we can overwrite what is in the total field. I cannot get this done, it says it's editable in "fotrmat>field format>allow entry into field", but it won't let us enter another amount. HELP!

brilliant!! Thank you...and I make a transparent number box over the automatically entered total to enter by hand other amounts!

quote:

---

Originally posted by livingwithanangel:

and I make a transparent number box over the automatically entered total to enter by hand other amounts!

---

Ack! Put the number field UNDER the calc field, not over it (i.e "behind" not "in front"). Make sure the calc field has "allow entry..." disabled. That way, when you click in what appears to be the calc field, you'll get the number field underneath.