Kyodo News is reporting that an economist was scanning Japanese Q4 2012 GDP data when he caught some egregious mistakes and reported them to the government.

As a result, some huge revisions were just announced to Q4 GDP, inflation and trade:

  • Annualized nominal GDP was corrected to -0.5% from -1.3%
  • Nominal quarterly GDP revised to -0.1% from -0.3%
  • Exports -1.7% vs -1.3%
  • Imports +0.5% from +3.0%
  • GDP deflator to -0.2% from -0.4%

This is as bad as Rogoff-Reinhart. Businesses and central banks are making enormous decisions based on these numbers and someone in Tokyo didn’t double check the numbers.

Japanese GDP numbers miscalculated