PL, SL need to deduct based on financial year (Apr - Mar)

Dear Team,

My client's PL, SL is calculating based on calendar year (Jan - Dec), but now management decided that from 01.04.2014 onwards PL & SL calculation
should be based on financial year (Apr - Mar),

So, kindly provide the details what are the changes need to be done to change leave calculation from calendar year to financial year.

Thanks & Regards

Prabu