This would be pretty tough to get within the Analytics UI, but I could see it reasonably working within Report Builder. It would require some implementation changes, though.
First, you'd want to implement an eVar that is populated with publish date. You could also create a classification of publish date which would be retroactive, but that might be a pain to maintain. You'll want to ensure Excel can understand and recognize the date format you put it in.
Once you have publish date as available data somewhere, create a data request in report builder with the following:
Blog post name (column A)
Broken down by publish date (there should only be 1 per blog post - column B)
Page views as a metric (column C)
This should create a simple request that shows the top blog posts, their respective publish date, and how many page views it has during whatever date range you specify.
Column D would be a date difference formula, so something like "Today minus column B" - this will give you the number of days the blog post has been active
Column E would have the data you're looking for, which would be column C (page views) divided by column D (number of days published).
From there you can schedule the workbook to be sent to you on a regular basis. The only thing that you'd need to do at that point would be to sort by column E instead of column C, since Report Builder only sorts by Analytics data.