
As the manufacturing sector continues to recover, inventories are on the rise. For example, inventories of manufactured durable goods rose for the 25th consecutive month in January 2012, according to the U.S. Census Bureau. For nearly two years during the recession, manufacturers have tried to satisfy demand from existing inventories whenever possible. Many manufacturers now will need to re-familiarize their operations with inventory-management practices as they and their markets enter a growth mode. For some, inventory management will be entirely new.
A majority of U.S. manufacturing plants do not use many common inventory-management practices and techniques: just-in-time supplier deliveries are the most common inventory-management practice (in use at 44% of plants), followed by pull systems with kanban signals (38%), and vendor-managed or -owned inventories (38%), according to the 2011 MPI Manufacturing Study. (Plants outside the United States were even less likely to be using most of these practices.) Approximately 17% of U.S. plants use none of the practices identified by the MPI study.
| Practice |
% of plants |
| Just-in-time supplier deliveries |
47.30% |
| Pull systems with kanban signals |
46.40% |
| Vendor-managed or -owned inventories |
42.70% |
| One-piece flow techniques |
24.10% |
| Quick equipment changeovers |
23.60% |
| Production leveling/heijunka |
18.60% |
| Parts/goods supermarkets |
18.60% |
| RFID and computerized inventory tracking |
10.00% |
| None of these |
16.80% |
Source: 2011 MPI Manufacturing Study, U.S. plants
In a rush to satisfy reemerging customer demand, manufacturers are unlikely to allow inventory shortages — raw material and components that go into their products or finished-goods — to prevent them from filling customer orders. And satisfying customer orders should be the first objective. But at what cost will manufacturing executives grow their inventories beyond rational levels of safety or buffer stock and risk profitability? Obsolete inventory was 2% (median) and 5.4% (average) in 2011. More is not necessarily better.
by George Taninecz, VP of Research, The MPI Group