How do I decide new currency?
 
It actually depends on the country based on your location. You have to follow the local currency of your own country. 
 
First you should know the business requirement of your client.
 
For example:
 
In the case where a new country is formed or if a country changes its currency we will get requirement to create a new currency. It happened in Europe when they started using EUR.
 
Define a new currency in customizing with transaction OY03 :
 
If you change the current currency, your accounting documents will be re-evaluated by R/3 and this could cause adverse impacts to your financials figures (This you need to clarify with your SAP Finance Consultant).
 
Use the following relevant Transaction:
 
OY04 - To Assign number of digits to new currency.
 
OBBS - To define conversion factor for currency conversion
 
OB08 - To enter exchange rates
 
XK02 - To assign new currency to vendor master
 
ME11 - To create a Purchase info record
 
Created MM documents with new extended price.

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