The Big Bang Theory, a situation comedy featuring Johnny Galecki, Jim Parsons, and Kaley Cuoco, is one of the most-watched programs on network television. The first two episodes for the 2011-2012 season premiered on September 22, 2011; the first episode attracted 14.1 million viewers and the second episode attracted 14.7 million viewers. The following table shows the number of viewers in millions for the first 21 episodes of the 2011-2012 season.
Air Date September 22, 2011 September 22, 2011 September 29, 2011 October 6, 2011 October 13, 2011 October 20, 2011 October 27, 2011 November 3, 2011 November 10, 2011 November 17, 2011 December 8, 2011 Viewers (millions) 14.114.714.613.613.614.914.516.015.915.114.0 Air Date January 12, 2012 January 19, 2012 January 26, 2012 February 2, 2012 February 9, 2012 February 16, 2012 February 23, 2012 March 8, 2012 March 29, 2012 April 5, 2012 Viewers (millions) 16.115.816.116.516.215.716.215.014.013.3
d. Has viewership grown or declined over the 2011-2012 season? Discuss.