Get value for last date regarding selection for this date

[#1]

HI all,

Please help me solve my 2 issues:

I have data for ex:

Date amount account

2010-01-01 1 1

2010-01-10 2 1

2010-01-20 3 1

2010-01-21 4 1

2010-01-01 10 2

2010-01-15 2 2

I join it with Calendar so i have all dates (for some there is no data on accounts).

I created a pivot table for example :

Account, date, amount.

1 .I would like to recived only one value for each account based on date which i select , but if operation doesn't exists for selected date i would like to recived last value (for max(day) < current selection for this account). For example

I select 2010-01-15 :

account date amount

1 2010-01-01 2

2 2010-01-15 2

2. After each reload i would like to recived results based on current date, but user can change it for any past date.

Regards,

[#2]

IN example should be:

Account date amount

1 2010-10-01 2

2 2010-01-15 2

There was wrong date for 1 account

[#3]

To last operation date i'm using

=date(aggr(nodistinct max({$<[Data transakcji]={'<=$(Data)'}>} [Data transakcji]),Konto))

But i can not create set for amount for this date, for example user select a 2010-01-19 i recived (with set) last operation date which is 2010-01-10 (for 1 account) but i can not recived amount for this date which is 2.

Please Anyone?