Keyword density has always been a topic of discussion in SEO and internet marketing forums. The reason why it is deemed important is because in the older days, keyword density was one of the most important factors to attend to.
A couple of years ago, if you wanted to rank high for a specific keyword, you would stuff in your keywords in the title tag, description tag, keyword tags and also in the content area. And there it was: number one in the searchers.

But times changed. Density wasn't important anymore but now, keyword density is a back as a measure to indicate your sites' relevancy. Searchengines do not give a lot of credit for undertaking measures to increase density solely, you have to have a good prominence too.

Instead of counting keywords and checking the keyword-density yu should write just good, convincing content which will force your readers to come back to read more of your articles. We will determine wether the the density AND prominence is balanced.

Prominence

Prominence of your keywords will have an impact on ranking your website in Google. Prominence refers to how relative a keyword is to the beginning of the website. The location of a keyword in the web page is becoming extremely important.
The higher up in the page a particular word is, the more prominent it is and thus the more weight that word is assigned to by Google when that word matches a keyword search done by a search engine user.

Consequently, it's best to have your important keywords in the first paragraph. Because your source code and the density play even as big parts in ending up as high as possible in Google you need to gather professional information.