Post ACY only in GL Journal

hollydonut

Hi All,

i am trying to find a way to post GL only for ACY only.
this is because my company want to turn on the ACY but also want the
old entry show in Balance ACY.
I have check there "Addtional Currency Posting" in gl journal. it is option field with value of None, Amount Only, and Additional Amount Only.
Can someone explain what is this?

thanks in advance