Schroe der, Bar kley, and Schroe der did not re- port price elas tici ties or the ef fects of other struc- tural changes on per cap ita con sump tion. Del gado and Cour bois (1998) es ti mated ex pen di ture, price, and ur bani za tion elas tici ties based on data from 64 de vel op ing coun tries for 1970–95. They used a sys tem of equa tions that sorted out rela tive price effects among ani mal prod ucts and that con trolled for many cul tural, geo graphic, physi cal, and eco - nomic dif fer ences be tween.
