On October 15, 2012, the board of directors of Ensor Materials Corporation approved a stock option plan for key executives.

On October 15, 2012, the board of directors of Ensor Materials Corporation approved a stock option plan for key executives. On January 1, 2013, 28 million stock options were granted, exercisable for 28 million shares of Ensor's $1 par common stock. The options are exercisable between January 1, 2016, and December 31, 2018, at 80% of the quoted market price on January 1, 2013, which was $15. The fair value of the 28 million options, estimated by an appropriate option pricing model, is $6 per option. 2.8 million options were forfeited when an executive resigned in 2014. All other options were exercised on July 12, 2017, when the stock's price jumped unexpectedly to $27 per share. When is Ensor's stock option measurement date? Determine the compensation expense for the stock option plan in 2013. (Ignore taxes.) (Enter your answer in millions.)