Well, that depends on how much others have invested, you get a proportional share.

However, the truth is in any case you do not get a lot. So if you are after revenue, you are much better off investing into a bid bot. Yet, if you want to invest into improving Steem then this is a (to my humble opinion as the dev :-D) very fine investment.

If you are really into the exact numbers, with this tool you can check the exact delegations to @trufflepig by others and compare with @trufflepig's daily rewards.

My gut feeling would say you could currently expect between 1 and 5 cents a day. But again, @trufflepig is not about revenue, but rather about promoting content and improving Steem. So better see any delegation as a donation for which you can get a small (tiny?) thank you.