Nov. 23 2012 05:00 AM

Average annual output per dairy has more than tripled in 20 years.

In both good times and bad, U.S. dairy producers keep cranking out more milk per herd. Here's what we mean:

• In 1992, average total milk production per dairy in the U.S. was 1.15 million pounds.
• In 2011, average total production per dairy was 3.81 million pounds.

Bigger herds are part of the reason; average U.S. herd size during that period soared from 75 head to 179. More milk per cow is the other part; average production jumped from 15,415 pounds per cow per year to 21,345 pounds.

For dairies both big and small, production growth on a large scale doesn't just happen. More facilities and employees don't magically appear, and the number of hours in a day doesn't change. Three times more milk per farm sounds great, but the higher costs that come with it mean greater reliance on banks and borrowing. Sooner or later, growth that averages 6.5 percent per year becomes a balloon of pressure on management. Some dairies pop.

Compared to the West, by the way, the rest of the county is hardly growing at all. Since 1992 average milk production per year per herd in the Midwest has almost tripled. In the Southeast it has doubled. In the Northeast it has almost doubled. In the West, however, it is almost six times higher. No individual state comes even remotely close to Idaho, where average production per year has increased more than 11-fold.

Even for herds that have always tended to be big, a many-fold increase in production presents huge growing pains. As the financial crises of 2009 and 2012 have made clear, none are more pressing than feed – do producers grow enough, is more land available, is feed available, and if it is can they afford it?