Forms - Visibility Macro

Hi,How to write a macro in @Visibility Condition@ (under @Forms -@ Field advances settings@) to field to display only if current visitor country is USA. I tried using this macro @Current visitor's country is one of the following countries: USA@ but not working.Here is my scenario,I have two contact number fields in my form, one is US contact number which should display only if the current visitor from USA otherwise it should hide.Another is International contact number which should display only if the current visitor is not from USA.Please advice how to implement this.Thanks in advance.