OTTAWA, Ont. — Factory shipments fell for the first time in three months in January as petroleum refiners and manufacturers of transportation equipment, principally automobiles, extended maintenance down-time into the New Year.

Manufacturers shipped goods worth an estimated $48.6 billion in January, down 2.1% from the previous month and 2.1% less than in January last year. January’s decline put the brakes on back-to-back rallies in the last two months of 2006, and completely wiped out gains made in December.

Overall, shipments fell in 12 of 21 sectors, representing 57% of total output.

Maintenance down-time beyond the normal holiday break for workers on car and truck assembly lines put the brakes on following a fourth-quarter comeback in the transportation equipment sector.

Companies in the transportation sector shipped $9.6 billion worth of goods in January, down 6.0% from $10.2 billion in December, which had been the highest level in a year. Transportation companies also reported a $990 million decline in new orders in January.

The biggest decline in the transportation sector occurred among car and truck manufacturers, whose output tumbled 8.0% to $5.1 billion.

Shipments of durable goods dropped 2.8% to $26.7 billion following a strong fourth quarter last year. Shipments of non-durable goods fell 1.3% to $22.0 billion thanks to the decline in the petroleum and coal sector.

Shipments of petroleum and coal products were down 8.1% in January, partly because of a 4.0% drop in prices, coupled with lower volume shipments from Canadian refineries.

Excluding the impact of the declines in transportation equipment and petroleum and coal, shipments in all other industries edged down 0.2% on small and widely dispersed movements.

The inventory-to-shipment ratio increased to 1.30 from 1.27 in December. The ratio had reached a peak of 1.33 in October, rising for three consecutive months before slipping in November.

Compared to a year ago, manufacturers shipped $1.2 billion less in January 2007 while holding nearly $1 billion more inventory. Finished product inventories stand $317 million higher in January 2007 compared to a year ago.