Thanks for the suggestion but I might have been a bit unclear :)
I want to show the values month for month, not on a total for the first six months ie HalfYear just that i want it in two different tables.
This is because I want to optimize the usage of space on the screen and also in printed pdf reports. A full year goes off screen.
Or am I missing something in the suggested solution?
Perhaps this, then, again in your script:
if(Month<7,Month) as FirstHalfMonth,
if(Month>6,Month) as SecondHalfMonth,
Then just use FirstHalfMonth in your first table, and SecondHalfMonth in your second table. You then don't need to check the suppress when null, which may help you out some trying to get what you want. It should also be much more efficient than a calculated dimension.