0CAL Month and 0Fisical Year.

Hai Pals,

what is 0CAL Month and 0Fisical Year... where we can define these objects..

whether these are keyfigures or charecters...

everyone said that for generating month wise report we need this fields.. but where we can define these objects.. and in the infosourse level also.. is it required to define in the Tranfer Strucures ?

plz help me..

thnaks

AK