I know I Adsense has Smart-Priced my Adsense account and this is the reason why my Adsense earning dropped by 50 percent.

And to understand more about the Adsense Smart Pricing here’s a compiled answers of Eric Giguere who is one of the Adsense experts at this time, from the Digital Point forums:

1. Smart pricing gets readjusted on a weekly basis. If you think you’re suddenly being smart priced, try and figure out why it might have happened. If you’re getting a temporary influx of poorly-converting traffic, say, then things will readjust themselves quickly once the traffic dies off. If you made some changes to your sites that are leading to more clicks for you but less conversions for the advertisers, that might be the culprit.
2. Do I recommend setting up separate accounts? That’s somewhat of an extreme reaction, but it’s certainly possible. You’d have to weigh the pros and cons to see if it’s worth the hassle of all the extra paperwork involved, though, and there’s no guarantee that all those separate accounts wouldn’t themselves be smart priced.

   If you’re doing dodgy stuff, setting up a separate account for all your whitehat sites is probably a good idea, though. But not everyone who gets smart priced is being dodgy.

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