Agricultural products are generally necessities, with income elasticities less than 1. However, the larger income elasticities for apples and cream mean that consumption will increase more than proportionately with increases in income. Broiler chickens have changed from a luxury good in the 1950s to a necessity today, as evidenced by the decrease in the size of their income elasticity. And, as expected, chicken is a substitute good with beef and pork, because chicken has a positive cross price elasticity of demand with both of these products.