Really? It Costs $10 Million to Recover Emails?

One line that stands out for me, from the Mother Jones story about the recovery of the missing Bush White House emails:

“The Obama and Bush administrations have already spent over $10 million trying to restore missing emails—significantly more than the $5.2 million that Congress originally appropriated for the task.”

Does anyone think that number is awfully high? That’s 45 cents per every recovered email. Is that normal?