Start and End Dates need to be calculated date fields (formula) based on the Fiscal_Year_Start_Date__c field on the Account and the Fiscal_Year__c.
Example: If Fiscal_Year__c = 2013 and Account.Fiscal_Year_Start_Date__c = 7/1/1990, Start Date = 7/1/2013 and End Date = 6/30/2014
Fiscal_Year__c is of type Picklist Fiscal_Year_Start_Date__c is Formula field