Suppose the plan year is calendar year and there are 3 commencement dates: 1/1/2011, 1/1/2015 and 8/1/2019. The following vectors of previous commencement date (#BCDATE 98), current commencement date (#BCDATE 99) and next commencement date (#BCDATE 100) can be created in salary and service transformation expressions, Benefit Definitions, Accrual Definitions, and SubFormulas.

 

                (Previous)    (Current)       (Next)        
   #DATE        #BCDATE 98   #BCDATE 99  #BCDATE 100
   ...
   12/31/2009   01/01/1900   01/01/1900   01/01/2011
   12/31/2010   01/01/1900   01/01/1900   01/01/2011
   01/01/2011   01/01/1900   01/01/2011   01/01/2015
   12/31/2011   01/01/1900   01/01/2011   01/01/2015
   12/31/2012   01/01/1900   01/01/2011   01/01/2015
   12/31/2013   01/01/1900   01/01/2011   01/01/2015
   01/01/2015   01/01/2011   01/01/2015   08/01/2019
   12/31/2015   01/01/2011   01/01/2015   08/01/2019    
   12/31/2016   01/01/2011   01/01/2015   08/01/2019   
   12/31/2017   01/01/2011   01/01/2015   08/01/2019    
   08/01/2019   01/01/2015   08/01/2019   01/01/1900  
   12/31/2019   01/01/2015   08/01/2019   01/01/1900   
   12/31/2020   01/01/2015   08/01/2019   01/01/1900
   ...   

 

Note that 01/01/1900 represents zero or none.