For a couple of months I have been receiving a lot of junk emails (sometimes a hundred or so per day) with the word [spam] in front of the messages on the subject line.

All of a sudden (within the past week,) my junk mail has decreased quite a bit and no longer receive any with the word [spam] in front of it. Now I get junk mail with the word [bulk] in the subject line.

I really don't mind the few junk messages I now receive (1 to maybe a half dozen or so,) but was just curious if anyone knows the answer?