It should be noted that to the best of our knowledge the "promptness in returning delivery receipts" variable has
never been reported as important criteria for carrier selection by any previous studies conducted in other countries. Our study found that suppliers of consumer goods gave fairly high weight to the time taken by carriers to return
the delivery receipts. There was a notable worry among the sellers of consumer goods in Thailand about the lost cash flow caused by the late possession of delivery receipts. Any delay in receiving this document from carriers would cause shippers the corresponding delay in collecting payment from their customers. The estimated parameters were subsequently analyzed to derive the economic prices of transit time and damage/loss occurrences as presented in Table 10. The damage/loss occurred to automotive parts was found to be more costly than that to consumer goods. The explanation for this is that the value of cargo in a typical automotive parts shipment is usually higher than that of consumer goods. Suppliers of automotive parts not only were more sensitive to but also placed higher value on transit time (or delivery speed) than their counterparts in the consumer goods industry. The criticality of transit time to shipments of automotive parts is certainly understandable, as these parts must be supplied in a just-in-time fashion to support
production activities in downstream manufacturers.