“Monday Effect” on Performance Variations in Supply Chain Fulfillment: How Information Technology–Enabled Procurement May Help

Abstract

If labor productivity varies in unknown ways over time, this could lead to unforeseen fluctuations in production or delivery rates, leading to stockouts or inventory build-up in a supply chain, while contributing to higher operating costs and to lower satisfaction levels for customers. The “Monday Effect,” that is lower productivity and higher error rates on Mondays compared with other days of the week, has been demonstrated in the finance and industrial relations literature. Using a database of 12 months of purchases from the General Services Administration (GSA) of the U.S. government (a key distributor of goods to government purchasers), we show that, indeed, performance is lower on Mondays compared with other weekdays in terms of order fulfillment and order cycle time. However, when purchasers use the GSA’s internet-based electronic market instead of using manual ordering procedures, the fulfillment gap between Mondays and other weekdays narrows considerably, demonstrating the value of information technology in smoothing distribution flows. By acknowledging the Monday Effect, distributors can thus plan for these weekly fluctuations and use information technology to improve service levels.