companies having US clients can't perform well due to dollar variation. but some companies have contracts from uk and other countries their prices will not affect with us dollar.

look,
it is right to say that software industry depends a lot on Dollar rate, but right now as the dollar rates are dipping most of the software giants are not performing well because they have to support a hugh infrastructure like thousands of employee hundreds of buildings and etc.One more thing there is a calculation as per which a fixed percentage of number of employee will always be on bench ready for any new coming project so this expense is huge while smaller companies do not have this expense thtswhy they are doing fair.
moreover the location of projects is also important .suppose if a company has all projects from US then it will be in greater loss than a compay which has some clients from US and some from japan.