Reporting its Q2 2013 results yesterday the firm revealed net sales up 17.9% in the quarter to $1.18bn - due to the acquisition of Central Europe operations, Eastern European brewer StarBev, in June 2012 - while underlying income after tax rose 11.4% to $278.6m.
The US is Molson Coors' biggest market by far, where it is the second-largest beer brand (behind AB InBev's Bud Light) in the world's second-largest beer market.
Strong growth in UK, Mexico
Canada only has one tenth of the population of the US, so volumes are much smaller, but Swinburn said: "Coors Light achieved mixed results by gaining share of premium lights in the US per Nielsen and is growing strongly in the UK and Mexico, but under-performing the market in Canada."
The brewer said beer volumes were hit by poor weather in Canada, while the company is cycling the launch of Coors Light Iced T a year ago, and new launches - Molson Canadian Wheat, Rickard's Shandy and Molson Canadian Cider - did not wholly offset these issues.
Weather and pricing pressures
CEO of Molson Coors Canada, Stewart Glendinning, told analysts: "June was an appalling month in beer volumes...wines and spirits were more or less flat, but beer itself was down across the country, and that was primarily driven by a weakness in weather.
"If you just looked at our volumes... we're off by about 100,000 hectoliters for the year, about half of that was Coors Light Iced T. So hopefully that gives you a little perspective," he added.
Glendinning said Molson Coors gained value share overall in Canada, but saw pricing pressures in the "very competitive" markets of Atlantic and Quebec.
He added that sales were down in premium segment and up in the value segment, while there was a shift towards consumers buying larger-sized packs.