Dow Movers: WBA, MRK

In early trading on Friday, shares of Merck topped the list of the day's best performing Dow Jones Industrial Average components, trading up 7.8%.

Year to date, Merck registers a 3.8% gain.

In early trading on Friday, shares of Merck topped the list of the day's best performing Dow Jones Industrial Average components, trading up 7.8%.

Year to date, Merck registers a 3.8% gain.

And the worst performing Dow component thus far on the day is Walgreens Boots Alliance, trading down 1.3%.

Walgreens Boots Alliance is showing a gain of 16.4% looking at the year to date performance.

Two other components making moves today are UnitedHealth Group, trading down 1.2%, and Walt Disney, trading up 2.4% on the day.