Mohammad Khoveyni - Department of Applied Mathematics, Shahr-e-rey Branch, Islamic Azad University
Gholam Reza Jahanshahloo - Science and Research BranchesIslamic Azad UniversityDepartment of Mathematics
Farhad Hosseinzadeh Lotfi - Science and Research Branches, Islamic Azad University, Department of Mathematics

The Malmquist productivity index evaluates the productivity change of a Decision Making Unit (DMU) between two time periods. In this paper, a method is proposed for computing the Malmquist productivity index in several time periods and then, the obtained Malmquist productivity index is compared with Malmquist productivity index between two time periods (the first and last time periods). When Malmquist productivity index is computed in several time periods, progress and regress of DMUs can be evaluated more careful than before. Finally, a real numerical example for illustrationpurpose is presented.

Data Envelopment Analysis (DEA); Malmquist productivity index; Efficiency