Annual national and regional milk cost of production estimates are updated twice a year, with preliminary estimates released in May of the subsequent year and final estimates released in October. These estimates are found here:

Commodity Cost and Returns

Annual milk cost of production estimates by State and by size of the operation are also published, and are found here:

Milk Cost of Production Estimates

ERS no longer updates the national monthly milk cost of production estimates.  The decision to stop publishing was primarily due to limitations of the data available to produce these estimates, which called into question their reliability.  An expert panel review of the ERS Commodity Costs and Returns Program recommended that these estimates be discontinued.  Monthly milk COP estimates by State are available from January 2003 through December 2010.  These estimates are presented as a historical record only and should not be used for analytical purposes.