Anomaly with Transaction SUIM

In Transaction SUIM,

for Users with Authorization Values

Object: S_TABU_DIS

Authorization Group : *

Activity : *

I get 217 User IDs

but, with

Object: S_TABU_DIS

Authorization Group : SC

Activity : 02

I get only 4 users.

But shouldn't this results be more than or equal to 217 ?????

Please help.