The following information has been obtained from the Myers Corporation:

300,000 shares of common stock were outstanding on January 1, 2015.

50,000 stock options were outstanding on January 1, 2015; each option allows the holder to acquire one share of common stock for $20 per share. The average market price of the common stock during 2015 was $25 per share.

48,000 shares of common stock were issued on February 1, 2015.

18,000 shares of common stock were repurchased on August 1, 2015.

What is the weighted average number of shares to be used in the calculation of basic earnings per share for 2015?

Format: xxx,xxx no unit, round if necessary.