Boost Leak Performance?

I was curious what others get on their boost leak test, i check mine from time to time just to make sure im still sealed up and to date its always been the same... i hook up boost tester to turbo, put my thumb over the CCV port on the valve cover, then i air it up with the compressor... i start at 25, 30, 35, then 40 for the final.. if i keep my thumb over the CCV port the only leak i get is via the oil cap... if i push down on the cap and keep my thumb on CCV port it will hold pressure well over a minute before dropping below 20psi...