GMM vs. GXY

So there is clearly a strong link between these 2 companies as seen by chart below.
Previously it looked like GXY was mirroring GMM perfectly but was just 6-8 weeks behind.
Now both seem to be following a short term identical downwards trend, which would make me think its market conditions or some external factor affecting both companies?
Is it possible there is news with both companies that some people know about that we dont't?

What are your opinions of these 2 companies back to back and do you think GXY has as much value long term as GMM?