Earnings per Share. The table that follows presents our computation of weighted average basic and diluted shares outstanding, which we use in our earnings per share calculations. For each period presented, our net income allocable to both common shareholders and diluted common shareholders is the same as our net income in our consolidated statements of income.



	Three Months Ended Mar 31,
(in thousands)	2016	2015
Basic shares outstanding	97,952	99,473
Effect of restricted stock units	334	439
Diluted shares outstanding	98,286	99,912

Our quarterly dividend to our common shareholders has been $0.27 per share since the second quarter of 2014. Our latest $0.27 per share quarterly dividend was declared in April 2016 and is payable in June 2016.

Share-Based Compensation. We have no outstanding stock options and, therefore, no share-based compensation to be recognized pursuant to stock option grants.

Through 2014, we granted restricted units of our common stock to certain of our key executives, key employees and Chairman of the Board. We also granted shares of restricted stock to our other non-employee directors. The restricted units granted to our key executives and key employees generally vest in full on the third anniversary of the award date, conditional on continued employment. The restricted stock unit grants, including those granted to our Chairman, can vest pro rata over three years, provided the individual meets certain age and years-of-service requirements. The shares of restricted common stock we grant to our other non-employee directors vest in full on the first anniversary of the award date, conditional upon continued service as a director. Each grantee of shares of restricted stock is deemed to be the record owner of those shares during the restriction period, with the right to vote and receive any dividends on those shares. The restricted stock units outstanding have no voting or dividend rights. In 2015 and 2016, we made corresponding grants to those described above, except we granted restricted shares, rather than restricted stock units, to our Chairman.

For each of the restricted stock units granted in 2014 through 2016, at the earlier of three years after grant or at termination of employment or service, the grantee will be issued a share of our common stock for each unit vested. As of March 31, 2016 and December 31, 2015, respective totals of 1,108,876 and 831,291 and shares of restricted stock or restricted stock units were outstanding.

We estimate that stock-based compensation cost not yet recognized related to shares of restricted stock or restricted stock units, based on their grant-date fair values, was $26 million at March 31, 2016. This expense is being recognized on a staged-vesting basis over three years for awards attributable to individuals meeting certain age and years-of-service requirements, and on a straight-line basis over the applicable vesting period of one or three years for the other awards.

Share Repurchase Plan. In December 2014, our Board of Directors approved a plan to repurchase up to 10 million shares of our common stock. Under this plan, we had repurchased 2.0 million shares of our common stock for $100 million through December 31, 2015. We did not repurchase any shares under the plan during the quarter ended March 31, 2016. We account for the shares we hold in treasury under the cost method, at average cost.