Just how much U.S. milk goes into U.S. dairy exports? A few readers posed that question after reading the October 10, 2020, Editorial Comment "Should we cull all the cows in Wisconsin?"

Measuring how milk converts to actual dairy products is not a perfect science. However, it's still rather robust.

Let's look at a different example before we turn to dairy . . . What is the temperature in Fort Atkinson, Wis.?

My friend from Europe says, "It is 8°."

My co-worker says, "It is 46°."

Both are right! It is 8° on the Celsius scale and 46° on the Fahrenheit scale.

Now let's turn to dairy. How much U.S. milk, via dairy products, was exported on a skim solids basis in 2019?

Data from USDA's Economic Research Service (ERS) tells us that the U.S. produced 19,502.4 million pounds of skim solids and had commercial exports of 3,709.9 million pounds or 19% of total production exported.

How much U.S. milk, via dairy products, was exported on a milkfat basis in 2019?

The U.S. produced 8,564.1 million pounds of milkfat and had commercial exports of 356.8 million pounds, or 4.2% of total production exported.

How can these numbers be different? The U.S. uses nearly all its milkfat for dairy products sold to domestic customers. That means the butterfat is "skimmed" from farm gate milk and the remaining milk components — skim solids — get turned into products largely made from skim milk solids.

Bottom line, using the 4.2% and 19% data points, we arrive at 14.5% of U.S. milk production was exported in 2019.

This information comes from audited USDA data. Every export has a deportation certificate. My thanks goes out Scott Brown from the University of Missouri's FAPRI (Food & Agricultural Policy Research Institute) who helped develop this answer. Brown routinely provides information to the House and Senate Ag Committees as it relates to dairy.