yes, I have considered that. and every source I can find puts dairy cows at about 3 years of production, calving for the first time at about 2 years old.

it’s possible your operation was not average, and most dairy cows only live 5 years.

anecdotes are not data.

https://albertamilk.com/ask-dairy-farmer/how-long-does-the-average-dairy-cow-live/

cows don’t naturally live to 20 years. they can live that long if they are well fed and watered and protected from disease, predators, and the environment. that’s an artificial life span.

hardly any dairy calves end up as veal.

thousands_of_head_of_cows = 9448.0
actual_cows = 1000 * thousands_of_head_of_cows
annual_male_calves = .5 * actual_cows
veal_weight_of_calves_in_pounds = 260
annual_veal_production_in_millions_of_pounds = 58
annual_percentage_of_bobby_calves_that_become_veal = ((annual_veal_production_in_millions_of_pounds * 1000000) /  (veal_weight_of_calves_in_pounds * annual_male_calves))*100
print(annual_percentage_of_bobby_calves_that_become_veal)

a dairy cows life span is like 5 years

most dairy calves are brought to full weight before slaughter.

most dairy calves are brought to full weight before slaughter, and the life span of a dairy cow is about 5 years.