I know that picking low ranking key words are better, but what is too low a keyword rank? For example 1 keyword I am looking at has a global monthly search of 500, would you write a hub with that, or find another key word?
I would never go below 500 and that would be the bottom line for me. I also do one other check before I would write this hub and that is to check the competition for a low search keyword like this. Put the keyword inside inverted commas in the main Google search page and hit enter.
If there are more than 50,000 competing pages then I wouldn't bother as the competition would be too high.
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