This research examines the historical evolution of prices paid to farmers for the most important agricultural products in Rio Grande do Sul for the last three decades, by giving special attention to the changes in prices that occurred since the nineties, and mainly after the monetary stabilization obtained with the "Plano Real" in 1994. The methodology used was the times series, based on longitudinal data collected by Emater/RS regarding the average monthly prices paid to farmers, from January 1973 to December 2005. The results indicated that all studied products (rice, beans, corn, soy, and wheat) had a significant decline in their real price values between the years of 1973 and 2005, and the biggest decline occured during the eighties. Besides, it was not identified a clear price trend for rice, wheat and corn in the period after the "Plano Real" due to the random pattern in price variation for these products. In this period, there was also a slight positive trend in the prices of soy and a decline in the prices of beans.
agricultural prices; livestock market; times series
