Reference Fields 

A reference field must be specified for a field with a currency amount.  A field is only assigned to the reference field at program runtime. For example, if a field is filled with currency amounts, the corresponding currency is determined from the assigned reference field -  that is, the value entered in this field at this moment defines the currency.

Proceed as follows:

       1.      Create a field in a structure using Add Element. In the Simple Type tab, choose the Browse pushbutton. Here you select the currency or currencyNormalized type in the com.sap.dictionary.predefined.currency package. Choose the currencyNormalized type if formatting should correspond to editing of currency specifications in R/3.   

       2.      Create another field and assign the Decimal data type.

       3.      In the Reference element field, enter the name of the field defined under item 1 above.