Cluster Table

Hi All

I want to use Cluster table ......following are the Query...

"Read CLSTR table b2, read sub table ZL looking for wagetype (LGART)= 9001. Cumulate field ANZHL for each entry where LGART=9001 for last 365 days including system date at runtime (system date and prior 364 days)"

i didnt work on cluster table...

Plz help me in solving this query..

Thnx

Rohit