As per your advice i have created two dep. key.
I have created two main asset. This two main asset i have assigned to one group asset.
I have assigned the different dep.key for IT dep for that two main assets.
But still it is calculating the dep for the whole year. Since i have posted the first asset as on 01.04.2008.
When i post the second asset on 01.12.2008. it is calculating dep. for whole year. But it suppose to calculate half of the percentage. (less than 180 days)
Please look in to this and suggest me to handle this issue.