My mom has kept feeders out for 40 years and she has built up quite a population of hummers.
She goes through two quarts of feed per day during peak times.
I have a half dozen or so regulars at my two feeders and can make a quart go a week.
BTW I have done side by side test and switched back and forth on the feeders and they definitely like my home made nectar better than store bought. One cup of sugar to 4 cups water or maybe just a little stronger on the sugar. They don't need any additional nutrients from the nectar, they get all they need from the bugs they eat.
Here is a great resource on hummingbirds and feeders.
Hummingbird Feeders