Retail food prices rose l0.9 percent in I 979, while the overall rate of inflation was 11.3 percent. These rates compare with a I 0-percent increase in food prices and a 7. 7-percent overall inflation rate in 1978. Retail food prices are expected to rise another 7 to 11 percent during 1980, with overall prices expected to go up 10 to 12 percent.