Global Payroll Interface Template - Nationality Three Country Code

Summary:

We are using the Global Payroll Interface Template to create an Extract that will send data to our Vendor, this extract sends CitizenshipDetails with a Nationality Attribute. This attributes returns a Two character country code however the Vendor only accepts Three character country code.
We tried doing the following to replace or modify the nationality attribute:

• Use Custom Fast Formula, though when we try adding the custom fast formula with type Extract Rule it is not showing in the Rule selection field. We noticed that only delivered Extract Rule can be selected in the extract.
• Use of Decode Database Item, we tried this method however the Decode field is limited to 2000 character which will not cover all the countries.