 Shares of Extra Space Storage Inc. EXR, -1.05 rose 0.4 in premarket trading after the real estate investment trust REIT that owns and operates self-storage properties raised its dividend by 20 to boost its implied yield above its peer group. The company declared a quarterly dividend of 1.50 a share, up from 1.25 a share, with the new dividend payable March 31 to shareholders of record on March 15. 