[T]he advance reading of real GDP came in at 3.2% for the 4Q of 2010 (actually, it was 3.17%, but who’s counting?) versus expectations of 3.5%. There was a lot of internal noise, with large positive contributions from personal consumption and net exports, offset by negative contributions from inventories and government spending. However, the line item that jumped off the page was the GDP deflator, the measure of inflation that turns nominal GDP into real GDP.
The GDP deflator was very light at only 0.3%. If it had come in as estimated (1.6% according to Bloomberg), and all other inputs remained constant, real GDP growth would have been cut in half. A smaller deflator pads real growth by subtracting a smaller number from nominal growth. We read one possible explanation for the light deflator: oil is an import, and imports subtract from GDP, therefore higher oil prices subtracted from the GDP price index. What we do know is that the core PCE price index (a preferred Fed measure of inflation) also declined, and the GDP deflator tends to track Core PCE over time despite the quirkiness of GDP accounting. The current level of Core PCE, 0.4%, is the lowest on record since 1959.So bottom-line, inflation under-reporting is inflating 2010 GDP estimates.