Industrial maintenance, repair, and operating (MRO) supply distributor W.W. Grainger (NYSE:GWW) today reported daily sales grew 8% in January from the year-ago period, but there were 22 selling days this year compared to 21 days in 2012. However, the first quarter of 2013 will feature one less selling day, or 63 days, versus the 64 selling days it enjoyed a year ago.

Greater volume accounted for 3 percentage points of the reported increase, as did higher prices, while sales of seasonal products and acquisitions each comprised 1 percentage point of the rise, according to the company.

Canada proved to have the best segment performance year-over-year, rising 10% for the month (8% in local currency), followed by the U.S. and its other markets -- primarily Asia, Europe, and Latin America -- both of which tied with 7% growth.