ssas - MDX query to have a snapshoot at a given date -

i have following fact table :

date       item   step value 2015-01-01 1      1     1.00 2015-01-01 2      1     2.00 2015-01-01 1      2     3.00 2015-01-02 1      2     4.00 2015-01-03 2      3     8.00 2015-01-05 1      3    16.00 

and i'm looking script find value of items in each step @ given date.

for example, date '2015-01-04', resultset :

step value 1    0.00 2    4.00 3    8.00 

i'm on sql server 2008.

===== update 1 make question more understandable

items can change of step can see in fact table, item in 1 , 1 step @ time. when calculate value of step, have sum value of each item present in step.

if in affirmative questioned in comment above, below might -

with member sumofvaluetillnow sum(null:[date].[date].currentmember, [measures].value)  select sumofvaluetillnow on 0 [yourcube] ([date].[date].[2015-01-04]) 

or, if looking value each date, below -

select sumofvaluetillnow on 0, [date].[date].children on 1 [yourcube]