In my country, the law states that vacations for an employee "resets" every 12 months, not calendar year like my zoho is configure right now. 

example: 

if i join a company August 1 2014 i have 14 vacations days to enjoy. The next 14 days will be acredited or rollover on August 1 2015. 

How can i set up my zoho to count vacations balance this way not per calendar year. 

Thanks a lot!