SSIS - Variable In Flat File Destination

Hi,

Here is my problem :
I work on a SSIS package with SQL SERVER 2005
I need to extract data from a table and put these data in csv files

But... the flat files name should be dynamic and assigned by a variable ...

Here's an example of my table :

Column header :
Id, Name, Number
1 TOM 22
2 TOTO 44
3 SAM 44
4 RADIO 55

I expect to have 3 csv files :
USER_22.csv
USER_44.csv
USER_55.csv

for example : USER_44.csv contains :
2;TOTO;44
3;SAM;44

if there's 50 different number, i expect 50 files

can i do that in a dataflow ?

thanks for answering