cryptid has pinned the tail on the Google Donkey sort of speak, the name of the game is higher and higher search worthy content as for Google's concerned, and if your articles are questionable, well then you definitely need to tweak them bad boy's a great deal to regain traffic.
Maybe even try tweaking your overall techniques as to use of tiling, keywords, and content placement as a whole, and if you've done such a thing already well maybe try to see if you've followed much of the guidelines that fit into the equation of what is identified by hubpages as a Stellar Hub.
I'll provide the link below, but all this is also found in the Hubpages Learning Center.
Good Luck and stick in there, all of us are suffering from the low traffic drops here on the web as a whole, so this means a great deal of re-work need to be done for sure if any of us are to survive the digital onslaught.
Official Hub Article on the "Elements of a Stellar Hub"
Bonus Help below as well "How to Augment Success with Self Optimization"