Hi Ahana,
Looks like in TCURX there is no entry for AUD, if there is no entry then SAP will treat it as Decimal 2 by default. Portal also it would get a default which would be 2 decimal places.
As you changed in its value in TCURX, you might have to do similar change even on portal BUT in portal you have to make the change in jar file ( com.sap.dictionary.runtime.mod_api.jar ) and when ever system is upgraded etc your changes will get reverted and you might have to reapply ur changes. Yes its bit head ace.
If possible better to leave it as is in TCURX i.e. let it get default 2 decimal places.
Regards
Yugandhar Reddy