1:00 pm : Despite a surprise downward revision to third quarter GDP, stocks started the session in higher ground and made their way to a fresh 2009 high with help from the latest existing home sales figures. Stocks have since surrendered some of their gains, but they remain in positive territory.

The third estimate for third quarter GDP was revised downward to a 2.2% annualized growth rate, which is below the 2.8% growth rate that had been widely expected and down from the 2.8% rate of increase posted in the previous estimate. That didn't undermine the positive mood among early participants, though. Instead, stocks started the session with broad-based gains.

The S&P 500 ran into resistance as it encountered its 2009 highs, but eventually pushed through the barrier to set a fractionally improved best for the year. The move came just a few minutes after the release of November existing home sales, which made a stronger-than-expected 7.4% monthly increase.

Stocks were unable to hold their highs as the Dollar Index made its way to a fresh three-month high, however. The greenback has since pulled back so that it now trades with a 0.1% gain against competing currencies. That pullback has helped stocks reclaim some of their gains.

There hasn't been much participation this session, given the low level of trading volume currently seen in the NYSE. Nonetheless, the general mood among equity investors remains positive; of the major sectors in the S&P 500, only utilities (-0.6%) are in the red.