< p> METRO INC. $37 (www.metro.ca) spent $355.2 million on share buybacks in the 12 months ended September 9, 2015. That’s equal to 4% of its $8.9-billion market cap. Under its new authorization, the supermarket operator can repurchase up to 7.4% of its outstanding shares by September 9, 2016. Buybacks raise earnings per share and other per-share calculations and give the remaining shareholders a larger stake in the company. Buy.