I have a question

Actually, other than passive wording, nothing is wrong, and even then passive writing can be seen as acceptable in technical writing.  You might want to change the scanning mode.  Just mouse over the "Start Review" button, and choose the type of writing you have.  In technical and business modes, it does not scan for passive voice.

To get rid of the passive voice, just say who is doing whatever action.  For instance if the sentence was:

The ball was thrown by John.

You could also say:

John threw the ball.

Both are correct but the first one is passive voice, since the object is being acted on by the subject (like I just worded the 2nd part of this sentence).  The second one is active, since the subject of the sentence is directly acting upon the object (what is usually the predicate noun) of the verb.

So back to your sentence:

According to CRM failure rates: 2001-2009 (Michael Krigsman, 2009), by 2006, the customers viewed more than fifty percent of all CRM implementations as failures.

I just reordered the sentence a little and removed the clause from the end, since only passive voice needs that clause to make it easier to understand.  So in this instance, active voice makes the sentence shorter.  You could even us over in place of more than if you want to make it shorter.