OTTAWA — Canadian transportation equipment sales retreated in September, causing overall manufacturing to slip 0.6 percent to $45.1 billion.

Sales in September fell in 13 of 21 industries, representing two-thirds of total sales.

Despite the decrease, Stats Canada reports manufacturing sales were 17.7 percent higher than their most recent low in May 2009.

Since then, sales have increased in 11 of the past 16 months.

The largest contributor to the decrease was the motor vehicle industry, where sales fell 10.4 percent to $3.6 billion due to lower production at several assembly plants.

Partially offsetting these declines were gains in the petroleum and coal products industry (+6.2%) and the primary metal industry (+3.3%).

Inventories edged down for the first time in four months, although only by 0.2 percent.

Petroleum and coal products decreases were mostly offset primary metal and fabricated metal inventories.