WASHINGTON — The preliminary national average price received by farmers for all wheat in December was $6.45 per bu, down 81c from $7.26 in November but up 1c from $6.44 in December 2010, the U.S. Department of Agriculture said in its latest Agricultural Prices report.

The average price paid for winter wheat in December was $5.93 a bu, down 49c from $6.42 in November and down 47c from $6.40 in December 2010. The average price paid for durum was $10.40 a bu, unchanged from November but up $4.69 from $5.71 a year earlier. Spring wheat other than durum averaged $7.63 a bu, down 83c from $8.46 in November but up $1.03 from $6.60 in December 2010.

The average price paid for rough rice in December was $15.10 a cwt, up 60c from $14.50 in November and up $1.30 from $13.80 a year earlier.

The December index of prices received by farmers for food grains was 217 compared with the 1990-92 base of 100, down 8% from 235 the previous month but up 2% from 213 in December 2010.

The December index of feed grains was 238, down 6% from 253 in November but up 18% from 202 in December 2010. The average price paid to farmers for corn was $5.44 a bu, down 40c from $5.84 in November but up 62c from $4.82 in December 2010. Farmers received an average of $10.10 a cwt for grain sorghum in December, down 60c from $10.70 in November but up $1.31 from $8.79 in December 2010. The average price paid for oats in December was $3.31 a bu, down 5c from $3.36 in November but up 37c from $2.94 in December 2010.

The index of December prices received for oilseeds was 206, down 4% from 215 in November but up 4% from 199 in December 2010. Farmers received an average of $11.10 a bu for soybeans in December, down 60c from $11.70 in November and down 50c from $11.60 in December 2010.

The December index for dairy products was 152, down 3% from 156 in November but up 19% from 128 in December 2010. The average price for all milk in December was $19.80 a cwt, down 60c from $20.40 in November but up $3.10 from $16.70 in December 2010.

The December poultry and egg index was 163, up 6% from 154 in November 2011 and December 2010. The average price paid to farms for all eggs in December was $1.22 a dozen, up 20c from $1.02 in November and up 14c from $1.08 in December 2010.