OTTAWA — Manufacturing continues to remain relatively flat since January 2011, reports Stats Canada.

Constant dollar manufacturing sales declined 0.8 percent in May.

The overall decrease reflected a 2.4 percent decline in non-durable goods, concentrated in the food, petroleum and coal product and chemical industries.

Conversely, the durable goods industries rose 0.8 percent.

Overall, lower sales were reported in 11 of 21 industries, representing 71.9 percent of total manufacturing.

Meanwhile, inventory levels increased 0.7 percent in May to $63.1 billion, their highest level since April 2009. The rise was led by a 4 percent gain in the chemical industry, reflecting higher goods-in-process inventories.

Increased levels of inventories were also reported by manufacturers in the primary metal (+2.2%), motor vehicle (+10.4%), machinery (+1.0%) and aerospace product and part (+1.3%) industries.