This year is coming off to a strong start for Canada's fourth-largest bank, Bank of Montreal ( BMO). The $412 billion (in assets) firm has seen shares rally nearly 10% year to date -- not to mention its dividend payout of $1.40 in cold hard cash. BMO's hefty 4.67% payout hasn't been enough to curb heavy short selling, though. Shares currently sport a short interest ratio of 23.98, which suggests that it would take more than a month of buying for shorts to cover their positions at current volume levels. While BMO turned stateside years ago to take advantage of the excess returns being generated in the midst of the housing boom, the real jewel in this firm's crown is its Canadian retail banking business. With a tighter loan book in Canada and more enviable market share position than is enjoyed by its U.S. subsidiaries, it's clear that the lion's share of this stock's impressive double-digit margins are generated in its core business. Of course, that's not to say that all of BMO's eggs are in a single basket -- with its capital markets business making up more than a quarter of its top line last year, increased fee-based revenues offer attractive diversification away from banking. With impressive earnings and a well-capitalized balance sheet, this stock's payouts shouldn't be in question in the near-term, particularly if the Canadian dollar continues to outpace the greenback this summer.