What is Really “On-Time”? A Comparison of Due Date Performance Indicators in Production

On-time delivery is essential in today's dynamic conditions: if a company cannot produce and deliver on time, it has to make up for it by using high cost express delivery or faces customer dissatisfaction. One factor influencing the delivery reliability is the due date performance (DDP) within production. Although the significance of DDP has been established, the question of how to measure it remains. A review of existing literature shows the vast amount of different DDP measures (lateness, relative lateness, tardiness, schedule reliability, etc.). The purpose of this paper is to compare different DDP measures used in manufacturing in order to assess their interrelationship, so that companies are better able to understand the impact of their choice of measure. A review of DDP measures described in literature is performed, followed by statistical analysis of the relations between those measures computed on production feedback data from four real-world manufacturers. The results indicate that there exist differences across DDP measure groups. Further research is needed to assess the benefits of each measure in a given situation.