The primary goal of PW_Archives is to be light-weight and efficient. I've tried almost all of the popular archiving plugins out there, and so many of them make hundreds or even thousands of queries depending on the number of posts you have on your site. PW_Archives makes only one query to get your posts. That's it. Not only that but it doesn't do endless amounts of looping and counting to determine post and comment counts. That's all included in the one query it does, and it's very efficient.
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