In a broad retreat after three straight strong months, orders for new durable goods decreased 4.9% in July, the Commerce Department estimated Wednesday. This is the largest decline in new orders since January 2004. The outlook for business investment dimmed as core capital goods orders fell 3.7%, the largest decline since last October. The drop was sharper than expected. Economists had forecast a 1.5% drop in July durable-goods orders. Durable orders in June were revised to a 1.9% increase from the 2.8% rise previously estimated. Shipments of durable goods decreased 0.1% in July after two straight monthly increases. Transportation orders led the way in July, falling 8.6% after falling 1.6% in June. Excluding the often-volatile transportation goods category, July's new orders fell 3.2% almost reversing a 3.6% rise in June. Excluding defense, total orders fell 4.5%. The data on new orders and shipments of durable goods tend to be very volatile from month to month, so economists prefer to focus on longer trends spanning a quarter or a year. Year-to-date shipments - which feed directly into calculations of gross domestic product - are up 6%. Orders for computers and other electronics decreased 5.9%. Computer orders fell 8.3%, while communications equipment orders dropped 7.1%. Shipments of electronics increased 0.4%. Orders for machinery decreased 6.2%, while shipments fell 0.2%. In electrical equipment, orders fell 2.0%, while shipments rose 1.0%. Orders for fabricated metals fell 4.4%, while shipments fell 1.2%. Bucking the downward trend, orders for primary metals increased 1.1% as shipments fell 1.0%. Unfilled orders - a gauge of future production - increased 1.0%, the third straight monthly increase. Inventories increased 0.6% and have risen in seventeen of the last eighteen months.