So my rough estimate was only about $75 off?
Let's look at that $36/day figure, because I don't trust those blogs.
The PSU page puts the absolute top production for the Saanen at 4870lb per lactation period. Add in the gestation and you're getting 4870 lb per 433 days, or 11.25 lb per day -- 1.4 gallons per day average.
At $12 per gallon, that's $16.8/day per doe, or $6132 per doe per annum, for a grand total of $73k gross receipts per annum on your herd of a dozen.
That's if you can get the top of the market price for the milk, and if all of your goats produce at the absolute top capacity and you get them bred the day after they dry up (but in this case you should probably be breeding your wondergoats for sale, or making money selling semen from the wonderbucks).
One of the parts that the worksheet brings in is all the expenses - both fixed and variable. This is where there is a "yes, you could have a dairy goat heard and make money, but in order to make more money, you need to better vertical integration of the operation" which gets into the growing your own fodder which gets into other economies of scale and ends up looking more like a regular dairy operation growing oats whatever.
The "have a heard of goats, milk them twice a day and live off of that with lots of free time between the milking" isn't something that is easy to do.
---
https://www.thehappychickencoop.com/how-to-make-money-raisin...
> A goat farmer can earn $8 to $12 per gallon. The most profitable dairy goat breed is the Saanen, in which you can profit up to $36 per day.
From https://backyardgoats.iamcountryside.com/goat-breeds/nubian-...
> Productivity: Average 6.6 lb. (3.9 kg) milk per day/1920 lb. (871 kg) over 305 days with 4.8% butterfat and 3.5% protein. ... Although yield is lower than for most dairy breeds, the high levels of milk solids impart a rich flavor and improve coagulation, making it an ideal constituent for making goats’ cheese.
Compare with https://backyardgoats.iamcountryside.com/goat-breeds/saanen-...
(digging) - this gets to https://iopscience.iop.org/article/10.1088/1755-1315/640/3/0... - the saanen appears to be about 15% - 30% more milk in the same time frame depending on the source.
The "sample dairy goat budget" on the page you provided is an interesting resource.
The price for goat milk - https://milklife.com/articles/nutrition/differences-between-...
> ... For about a quarter per 8-ounce glass, cow milk offers more nutritional value than just about any other beverage you can buy at this price. Goat milk is nearly five times more expensive, ringing up for $1.24 per 8-ounce glass.
The budget worksheet puts the milk at $6.50/gallon.
My math was based on a that very rough $36/doe/day math without accounting for expenses. I was interested in the "is the herd size a dozen? two dozen? or a hundred? ... in order to live ok?"
The worksheet puts a rough estimate of the total receipts which the worksheet puts at $1,323.10/doe/year.
The returns over variable costs per doe per year is $359.01 and returns to management is $225.72.