摘要：The cyclical nature of numbers and prices of sheep and lambs was examined from 1924 through 1993. Tests for structural change also were conducted utilizing the minimization of Akaike's information criterion (MAIC). Results indicate that cyclical length in both stock sheep numbers and lamb prices has decreased over time, with a current 10- and 27-year cycle in stock sheep numbers and nine- and 27-year cycle lamb prices. Structural changes occurred in 1951 and 1968 for stock sheep number and in 1952 and 1972 for lamb prices.
