Why is the rankings for certain targeted keywords dropping sharply in the past few weeks?

[robotseo]

Excuse me here I can't reveal the website url here due to the confidentiality.

Background:

This website has about 100+pages, and is a wordpress site. Out of 15 targeted keywords, there are few ranked first on Google.co.uk. others are ranked between 3rd and 50+. In the past couple of weeks, we have been submitting to various websites/directories. and 4 main keywords' rankings are improving steadily from 50+ to 20+. We don't buy links, or pay for link exhcanges. We only exchange links on rare occasions.

Symptoms:

1. 2 out of 4 main keywords dropped its rankings from 20+ to 80+ 4 weeks ago over night.

2. We kept on acquiring links from directories and websites, and 2 weeks after the drop, the rankings of 2 affected keywords had gradually made its way back to 20-30. Just we thought the glitch was over, these 2 keywords has dropped rankings to 50+ once again.

3. The change of rankings looks too suspicious to us, so we went to use the Moz tool, and discovered the domain authority has also dropped 25% of its value in a month time.

We never experienced such violent changes in terms of rankings in such a short period of time. My question is: what factors there are to have caused such violent shifts? Why the value of the domain authority is dropped by 25%-30%? What elements affect the domain authority the most?

[irvingw]

Sounds like you're getting hit by panda. How robust is the content on the pages across your site?

Directories are no longer a recommended method of link building. Without the URL it's hard to make a determination as to why you got hit.