NASA on Shuttle Costs

At USA Today Dan Vergano has an article taking a look back at the Space Shuttle program, which is scheduled to fly its last flight this year.  I chatted with Dan yesterday about the program and in particular the difference between the estimates that NASA provided to him of total program costs, $113.7 billion, and those that Rad Byerly and I recently published, $192 billion.

My first impression was that NASA did not adjust for inflation in their tabulation (what the students in my quantitative methods seminar this past term learned was a methodological no-no).  Dan did a follow up and this was indeed the case. Here is an excerpt from the email that Dan received from NASA Public Affairs, shared with Dan's permission (emphasis added):

The number I gave you is actual dollars (that is we added the dollar amount for each fiscal year and came up with a total). The author [Pielke] seems to have adjusted his numbers to 2010 dollars then added them up. Because we don't know how he computed his adjustment, we can't comment on how he arrived at his number.

We estimate the total cost of the program in 2010 dollars from FY1971 to FY2010 (which does not include STS-133, STS-134 or STS-135) would be about $209.1 billion.

I'm not sure what is in NASA's numbers that is not in ours, or how they computed the inflation adjustment, but we did our calculations conservatively, so I'm not surprised at the higher tabulation. However, this is the first time in the 20 years that I've been looking at this issue that NASA reports a higher number than we do -- the per-flight difference is small -- $1.6 billion per flight from NASA and $1.5 billion from us, so not a big difference, but it is nice to see a convergence of views.