S&P 500 Movers: BIIB, LLY

In early trading on Thursday, shares of Eli Lilly topped the list of the day's best performing components of the S&P 500 index, trading up 8.3%.

Year to date, Eli Lilly registers a 39.3% gain.

In early trading on Thursday, shares of Eli Lilly topped the list of the day's best performing components of the S&P 500 index, trading up 8.3%.

Year to date, Eli Lilly registers a 39.3% gain.

And the worst performing S&P 500 component thus far on the day is Biogen, trading down 5.5%.

Biogen Inc is showing a gain of 43.6% looking at the year to date performance.

Two other components making moves today are Dollar Tree, trading down 2.5%, and MGM Resorts International, trading up 3.8% on the day.