The “University of Wisconsin recommendation for growing corn is 160 pounds N per acre.

So if you use a solid dairy manure spread at a rate of 25 tons per acre will provide 75 pounds of N per acre.

So to get the 160lbs of N needed for the soil - 53.3 tons of manure is needed - about 4 double decker’s worth

(updated manure wholesale price) Manure ranges from $14 to $24 per ton.

https://www.drovers.com/article/what-economic-value-cattle-manure

Let's use $19 as an average.

53.3 tons manure for 19 dollars/ton manure = $1012.7
15,000,000 calories / 402.6 dollars = 14811.889 calories/dollar

Assuming you only lived of this corn, you would be generating

1$ to animal AG/7.4 days assuming 2000calories/day.

20 years on this diet
$986 to animal AG

a Lifetime on this diet (27375 days average)  $3,699 to animal AG

Using the ratio of 80%/20% based on synthetic fertilizer usage vs manure usage to get a ratio of 4:1

The numbers for conventional are:

1 dollar to animal AG per 37 days assuming 2000calories/day.
20 years on this diet = $197 to animal AG
Lifetime on this diet (27,375 days average) = $739.8 to animal AG
Organic corn: Lifetime on this diet (27375 days average) = $3,699 to animal AG
Conventional Corn: Lifetime on this diet (27375 days average) = $739.8 to animal AG
Difference: $2,959 to animal AG
How does this compare to Milk?

Daily difference in demand: (1/7.4)-(1/37)= $0.1081/day

https://www.ams.usda.gov/mnreports/dymadvancedprices.pdf

Class 1 base price $16.99 per hundredweight

Convert to daily demand: ((16.99/112lbs)*8.6lbs/gal)/16cup/gal = $0.0815

Therefore, the daily difference in demand using a corn steel-man shows that an organic diet compared to a conventional diet generates more demand to animal AG than drinking 1 cup of milk per day.