The question of how much booze dwarves need to drink has come up a couple of times recently, and has been answered by someone saying they think that someone else said that dwarves need 16 drinks per year. Since nobody seemed certain, i decided some science was needed.
I started out 7 dwarves with:
4 Picks
2 Battle Axes
28 Dwarven Beer
28 Dwarven Wine
28 Dwrven Ale
28 Dwarven Rum
112 Plump Helmets
The total number of booze was chosen as 112, the predicted consumption for 7 dwarves in 1 year.
They immediately chopped down a couple dozen trees, dug a modest fort, moved everything but the animals inside, and walled up the entrance. The animals were left pastured outside. They then proceeded to carve out a nice home with a 3x3 room for each dwarf and a 11x11 dining hall, then smoothed and engraved the rooms and hall. The digging, stone dumping, smoothing, and engraving kept everyone pretty much 100% busy for exactly 6 months (purely by coincidence, I didn't plan the timing). After that I gave them nothing to do and they just sat around for 6 month. They had no access to water and did not do any farming.
At the beginning of every month (approximately), I recorded how many booze and plump helmets were remaining. Sometimes I was a few days late, but I always recorded the exact date. Starting in Felsite (the 3rd month) I also recorded how many plump helmet spawn were in stock, just to see how many I was getting from each plump helmet.
When migrants showed up, I set up a 1 tile meeting "hall" outside and let them sit out there. I expected them to either starve or get killed, but most of them survived by hunting and eating vermin. There were eventually 11 or them, and I organized them in 2 squads so they would defend themselves. One migrant arrived with a pick, which added immensely t their survivability. They managed to kill a couple of ogresses and a few harpies, but a werewolf did manage to get a few of them isolated and killed them. But they weren't important to the science, since they were completely isolated from the original 7.
Inside the fort, the booze slowly dwindled, and the food did even more slowly. The final drink was take on the 8th of Obsidian (the 11th month), nearly a month earlier than expected. As of that date, the dwarves had drunk at a rate of 16.72 drinks per year per dwarf, or one drink per 20.09 days for each dwarf. I strongly suspect the actual value is one drink per 20 days on average. But the rate did fluctuate over time, so there is probably a random factor tossed in.
On the 8th of Obsidian, the food was down to 53 plump helmets. That's a rate of 8.99 per year per dwarf, or 37.37 days per plump helmet for each dwarf. But see below for a possible problem with these numbers.
The number of seeds per plump helmet varied a lot, and sometimes the number of seeds fell from one month to the next. There were a few vermin (rats and demon rats) around, and I'm sure they were eating the seeds. I was able to see a few times when a rat appeared in the same tile as a seed, and when the rat disappeared the seed was gone. It's also possible that they ate some plump helmets (but I didn't see any), so the actual rates per dwarf may be somewhat lower than my results would indicate. That might just raise the plump helmet rate to a nice round 1 every 40 days, but that's pure speculation. I doubt the vermin consumed any booze. If I were to do this again (and I'm tempted), I would bring a couple of male cats to keep the vermin under control.
My data is recorded in a spreadsheet
here.
As i said, I'm very tempted to repeat this with some cats to control the vermin. Any suggestions on other changes I should make to my test procedure?