Question on Currency conversion

The data from source system is coming with Local currency and reporting currency.

For some of the accounts such as goodwill, stock..we don't want the translation to be run again in BPC...

Hence for these accounts I have mentioned the rate type as NOTRANS/HIST. But translation blanks out the historical reporting currency amount.

How to make sure that some of the accout never gets translated, but is maintained as received from source system..

Appreciate inputs..