Level 02,Lag in custom measures

Hi,

We are on BPCNW10.SP level is 10.

We have a custom measure.Formula for this is:

IIF([%TIME%].CURRENTMEMBER.PROPERTIES("2/CPMB/CNPW963")="365",

((([MEASURES].[/CPMB/SDATA],CLOSINGPERIOD([%TIME%].[LEVEL02]).LAG(11))*30 + ([MEASURES].[/CPMB/SDATA],CLOSINGPERIOD([%TIME%].[LEVEL02]).LAG(10))*31 + ([MEASURES].[/CPMB/SDATA],CLOSINGPERIOD([%TIME%].[LEVEL02]).LAG(9))*31 + ([MEASURES].[/CPMB/SDATA],CLOSINGPERIOD([%TIME%].[LEVEL02]).LAG(8))*28 + ([MEASURES].[/CPMB/SDATA],CLOSINGPERIOD([%TIME%].[LEVEL02]).LAG(7))*31 + ([MEASURES].[/CPMB/SDATA],CLOSINGPERIOD([%TIME%].[LEVEL02]).LAG(6))*30 + ([MEASURES].[/CPMB/SDATA],CLOSINGPERIOD([%TIME%].[LEVEL02]).LAG(5))*31 + ([MEASURES].[/CPMB/SDATA],CLOSINGPERIOD([%TIME%].[LEVEL02]).LAG(4))*30 + ([MEASURES].[/CPMB/SDATA],CLOSINGPERIOD([%TIME%].[LEVEL02]).LAG(3))*31 + ([MEASURES].[/CPMB/SDATA],CLOSINGPERIOD([%TIME%].[LEVEL02]).LAG(2))*31 + ([MEASURES].[/CPMB/SDATA],CLOSINGPERIOD([%TIME%].[LEVEL02]).LAG(1))*30 + ([MEASURES].[/CPMB/SDATA],CLOSINGPERIOD([%TIME%].[LEVEL02]).LAG(0))*31)/365),

Any body explains me what is LEVEL02 and LAG.

NB:CPMB/CNPW963 is days in a year property for TIME dimension.

Thanks,

Manohar