IMO, there are reasonable sources of water in the bilge, and others that should be eliminated.
1. Conventional stuffing box that needs to drip a bit to work right.
2. Rain coming in through an anchor hawse pipe if your anchor locker drains into the bilge (doesn't count if your anchor drains overboard).
3. Rain coming in through the inside of a mast with in mast halyards.
4. Other vents for wet lockers that drain into the bilge.
5. Air conditioner condensation if it drains into the bilge (doesn't count if it drains overboard or into a sump).
6. Fridge drain (but you might want to plug this one, spilt milk in the bilge can get pretty nasty smelling fast, and cool air likes to run down hill).
Sources that should be eliminated:
1. Leaks below the water line such as thru hulls, hoses, strainers, etc.
2. Leaks above the water line such as poorly bedded deck hardware, chainplates, hatch gaskets, etc.
3. Hull/deck joint leaks (these repairs can be nasty).
As others have said, its more important to identify the sources as the "reasonable" ones than the exact amount of bilge water you experience, which may depend for example, if it rained. Finding above the water line leaks can be a painful experience. Wait for the rain or use a hose. At least in my experience, the place the water shows up is never obviously close to the place the water came in, especially when deck hardware is involved.
Oh, and I'm assuming we're not talking about wooden boats!