Hi Devesh,
In transaction OAYR you will find the check box "Smoothing"
In your case there should be a flag on check box "Smoothing"
If you remove the flag it will mean "catch-up". In your case, the system will calculate the difference in period 6.
The F1 help of this field will give a god explanation.
Deeper explanation you will have in note 1562637.
best regards
Bernhard