Predictions Are Hard, Especially About the Future, and Especially About Estimating the Excesses of Government Debt

James Pethokoukis at American Enterprise Institute's web site takes us back to yesterdecade to remind us that even the smartest and most expert of estimaters of future government debt can be very, very wrong:

 Here's the Congressional Budget Office's ten-year budget forecast from 2002 (note that this was after the Bush tax cuts were passed):….Instead of publicly-held debt as a share of GDP being a microscopic 7.4% this year [as they predicted then], it was closer to 74% – or 72.8% to be specific (as of the August update from the CBO.)

Peter Suderman's great January 2010 Reason feature on the problems with CBO predictions, on "the highly speculative nature of its work, which requires an endless succession of unverifiable assumptions."