ssas - Max value from Member Property -

i need max value of member property use in mdx expression.

as example adventure works i'm using following

    member dofp      [customer].[customer].properties("date of first purchase")    member maxdofp      tail     (       nonempty       (         [date].[date].[date]        ,[measures].[dofp]       )      ,1     ).item(0).membervalue  select    [date].[calendar year].[calendar year] on 0  ,{     [customer].[customer].&[20075]    ,[customer].[customer].&[15568]    ,[customer].[customer].&[20285]   } on 1 [adventure works]    [measures].[dofp]; 

i'd return june 15, 2008 rows/cols date of first purchase aaron alexander (who has max dofp of customers selected) can more calcs. instead giving me 31st dec 2010 because (i assume) that's last date in [date].[date].[date].

not pretty:

with    set x      {       [customer].[customer].&[20075]      ,[customer].[customer].&[15568]      ,[customer].[customer].&[20285]     }    member dofp      [customer].[customer].properties("date of first purchase")    member maxdofp1      max(dofp)    member maxdofp2      max     (       x      ,cdate([customer].[customer].properties("date of first purchase"))     )  select    [date].[calendar year].[calendar year] on 0  ,   x * {[measures].[maxdofp1],[measures].[maxdofp2]} on 1 [adventure works];