Prices of agricultural products often vary in relatively stable patterns around their long‐run trends. These variations translate into fluctuations of selling prices as well as farm revenues. We provide an overview of the current literature on agricultural price cycles. Using a transparent and reproducible model selection process and the Kalman filter, we select optimal models and estimate the cyclic patterns of hog and cattle prices for Brazil, Chile and Uruguay. Durations of those cycles are found to be about three years and seven years, respectively. These durations are in line with the literature and the biological characteristics of livestock production. Our results can inform producers forecasts on price developments in the short and medium run. They are useful for guiding policy makers on the timing of policy interventions for influencing the duration or the amplitudes of cycles.

中文翻译：

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南美牛和猪价格的周期

农产品价格通常围绕其长期趋势以相对稳定的方式变化。这些差异转化为售价和农场收入的波动。我们提供了有关农业价格周期的最新文献的概述。通过使用透明且可复制的模型选择过程和卡尔曼滤波器，我们选择了最佳模型，并估算了巴西，智利和乌拉圭的生猪和牛价格的周期性模式。这些周期的持续时间分别约为三年和七年。这些持续时间符合文献和畜牧生产的生物学特征。我们的结果可以为生产者提供短期和中期价格走势的预测。