David is probably right. There were two unusually large sales this afternoon and several smaller but still significant sales orders in between. It looks like some large institution was selling. It might not be over. It is doubtful that the sales were about PHK. Whoever was selling probably needed the money for something else.
I've had this happen from time to time about a dozen times with other funds I've owned. Its scary. Another fund I owned (HPF) once dropped $0.40 a share within seconds in a sudden selling spike and then later recovered over the next few days. My experience so far has been that it never has any lasting effect. After it ends the price recovers. While we don't know for sure who is selling or why in my opinion this selling probably has nothing to do with the fundamentals of PHK.