(Bloomberg) -- Royal Bank of Canada Chief Financial Officer Rod Bolger said the lender’s push to expand its business with mid-tier U.S. companies is exceeding its expectations.Toronto-based Royal Bank, through its City National U.S. private and commercial bank, began focusing on winning over mid-market companies less than a year ago to help expand its business south of the border. The strategy, which primarily targets private companies with revenue of less than $5 billion, fills a gap between Ci.