This question comes up all the time. Frankly, it is nearly impossible to answer without knowing exactly a lot of things about how you are using your stove. A lot of stoves can really throw some heat. This leads to buring a lot of fuel. Some stoves don't burn that hot. They use about half the fuel to start with. Priming always wastes a small amount. Some people use plenty and call it close enough. Some people use too little and have to prime twice. It can be hard to judge between the two on cooler morningings. Some stoves are remote, like the ones that Jim shows. Some are self contained, like the Coleman Sportsters...different priming needs. If you do a lot of cooking (bacon, eggs & coffee in the morning, soups for lunch and three course meals for supper) this will obviously take a lot more fuel than someone who only boils water once per day. Fuel usage can vary from less than a fluid ounce per day, to 2-1/2 fluid ounces per day in summer. In winter, more, of course. From solo trips to 3 person trips, it will vary. Soo, there is no one simple answer.
For myself, solo, I boil about a liter(quart) in the morning. This is enough for oatmeal, and coffee. I boil a similar amount at night, skipping lunch more often than not. I usually cook a stew, soup, rice or something at night. Sometimes foraged stuff is also available from the days hike. I plan on simmering stuff for at least 20 minutes in the evening. (I take many rest stops, about 5 minutes each. eating a handfull of nuts, a trail bar, some M&M's or the like, during the day, but I don't stop for lunch.) Generally, I use ~1fl ounce per day. A 10day solo trip will usually use a 12oz bottle of fuel, with a bit left over. With a partner, I bring a 16oz bottle.
Set up can make a HUGE difference in fuel consumption. I use an old SVEA 123 for all camping, 'cept 2-3 days. Then I use alcohol. For the SVEA I use a MIDI pump. This weighs about 1.25 oz, but weighs about the same as the fuel it saves for a week. I don't use a seperate prime, because it makes a mess of things and results in a big flame or fireball. Anyway, 5 strokes serves to presurize the tank. After fuel dribbles down the outside of the stem, I turn it off and light it. Just before it goes out, I turn the gas on and put the pot of water on. Then I adjust the burner to low. Low heat is far less wastefull of fuel.
In the morning (after dropping the tent, packing my bag and changing cloths) the water should be boiling. Even if it isn't, I turn it off...hot enough. I use treated water for the morning, soo, this is no problem. I have breakfast. then sit down with my coffee. After coffee, I pack my gear in my pack, clean up anything around camp, and leave. This usually takes about 1/3oz of fuel, depending on the temperture outside. This takes about 45 minutes. If I am in a hurry, I can skip all but the coffee. I NEED my coffee.
At night, I set up camp and again start boiling about a liter of water. After getting some wood for a fire, I usually make cocoa, then add ingredients for supper and let it simmer for about 20 minutes as low as I can get it. This uses up about 2/3oz of fuel.
Generally, I use a wind screen/heat shield around my old SVEA. The stove only puts out around 4500-5000BTU on max heat to begin with. On low, it is only about twice as good as an alcohol burner. On extreeme savings I can get this down to 3/4oz per day, but, that is a lot of fiddling. Knowing how much I burn lets me be very comfortable with the ammount I burn per day. The usage and consumtion will vary. Do your own test runs. My stuff has been dialed in over the past 30-40 years or so.
With a Simmerlite stove, I use about 3 times as much fuel. It burns hotter, and, it does not simmer as well. A 20oz bottle did NOT last for 7 days, 4 years ago when I tried it. Nice heat though.