Auto entering field from another field with tax

[alekmih]

Please help,

I want to make field to insert automaticly data from other filed but without tax (18%)

example
I have filed [Iznos] where the price is with tax and I want to make another filed where data will be entered automatically and without tax

I tried in "defaul value" to enter
[iznos] * 18/100
but don't works.

Thanks

 

[ajetrumpet]

I want to make field to insert automaticly data from other filed but without tax (18%)

I tried in "defaul value" to enter
[iznos] * 18/100
but don't works.

Well, first of all, you've got the formula incorrect. The one you want is this:

[iznos] / 1.18

...if you have a constant rate of 18%. If you don't, you'll need this:

[iznos] / (1 + [rateField])

I hope you're doing this stuff if forms. Instead of setting the default value for this, why don't you just populate it with a form event?