WMPT Nightly Business Report September 11, 2012
of the announcement. and, as suzanne pratt reports, all investors should be watching how the stock performs. >> reporter: it's known as the "apple effect." apple's stock is up; so is the broader market. apple shares fall; major averages drop, too. the world's most valuable company makes up nearly 5% of the s&p 500 index. thanks to apple's huge gain this year, the s&p is up 14%. on the other hand, the apple-less dow is up only 9%. and don't forget the tech-heavy nasdaq. apple accounts for 13% of the weighting in that index. thanks to the shine in apple shares, the nasdaq is up 19% thi...