Study on Fluctuation and Regulation of Potato Market Price in China: Based on the View of Stable Crop for the Potato

摘要

By utilizing the monthly potato market price data from 2011 to 2015 and time series model such as Xll seasonal adjustment method and H-P (Hodrick-Prescott) filtering method, this paper analyzes the period and rule of potato market price fluctuation. The study found that the peak of the National Potato Price Index appears around every May, the lowest point appears around every October, the highest and lowest points appear alternately each year. In the past 5 years, the potato price fluctuation in China is large, the fluctuation frequency is high, on the average, the drop of peak and valley variation rate is 42.18%, the average rising month for each cycle is 7.25 months, with an average cycle length of 14.25 months.