Filter a WEBI table based on Max(sting-value)

Hi experts,

I'm having some issues filtering a table on a dimension called Time:FY_FW.

The dimension contains the following values (data type string):

- FY17 WK30

- FY17 WK31

- FY17 WK32

- FY17 WK33

- FY17 WK34

The report should contain only the records with a max value (in this example FY17 WK34). I've tried the following:

- create variable =Max(Time:FY_FW) (BO will create a measure of this variable)

- create variable =If(Time:FY_FW = Max(Time:FY_FW);1;0)

- create variable in which I substring the FY and FW and subsequently took the Max value of it.

Unfortunately, none of the above seems to work as it continues to return al FY_FW records. Could anyone point me in the right direction?

Kind regards,

Chris Raes