Purpose - The purpose of this paper is to review the theoretical background, methodological extensions, and empirical applications of the Engel curve, which is applied to the research of the change in farmers' welfare and food demand in China after the economic reform in 1978, compared with the statistics of income and food consumption. Design/methodology/approach - This paper mainly uses the traditional method of Engel curve, which is compared with income growth and food consumption, to study farmers' welfare improvement in rural China. Findings - The Engel coefficients identify three different stages for farmers' welfare change after 1978. The first stage is the period between 1978 and 1988, in which farmers' welfare has been continuously enhanced due to the institutional bonus of the 1978 economic reform and increased government purchase price of agricultural products. The second stage is the period between 1989 and 1995, in which farmers' welfare has been slightly deteriorated mainly due to the end of institutional reform bonus, suppressed food prices, relative high inflation, and instable political situation. The third stage is the period after 1995, in which farmers' welfare returns to a growing path, as the dual price system was abolished, the transition from a planned economy to a market economy had been completed, and the government carried out protective policies for agriculture and started to heavily subsidize agriculture. The Engel coefficient still remained at a very high level at 0.59 in 1995, but it continuously decreased to 0.33 in 2015. The welfare enhancement for farmers mainly results from deepened market-oriented reform, protective policies for agriculture, and prevalent off-farm employment. The Engel coefficient is also linked to food demand elasticities. Along with the decreasing Engel coefficient in the past 40 years, income elasticities also continuously decrease from 0.55 in 1978 to 0.08 in 2015. Food demand is very inelastic now, and any further increase in income will not substantially increase food demand any more. Research limitations/implications - Inequality has not been analyzed. Originality/value - This paper reviews the methodological advantages of the Engel curves, and uses it to identify different stages of welfare change and estimate income elasticities of food demand for farmers in China after the 1978 economic reform.
