Leave automatic accrual

Hi Seniors,

I have query regarding time management

At client side they were maintaining time data and leave data properly till April but from April their automatic accrual is not working properly hence required your guidance.

I do have to keep last year leave balance data in the same and want to solve the query and upload new data which they have maintained in excel from May2010.

How to go ahead for the same to solve the problem.

Yuvraj