The S&P 500 is off to a great start for 2012, up 4.52% in the first 12 days of trading versus a 1.93% gain over the same timeframe in 2011.

But what about volume? I've seen a number of comments about the light volume of our "January Effect" rally. So let's do a comparison with last year. First, here is a snapshot of the index with the volume shown below along with its 50-day moving average.

According to the data I downloaded from my Stockcharts.com subscription, the cumulative volume of the first 12 days of this year is 36.39 Billion versus 46.10 Billion in the first 12 days of 2011. That is a 21.1% decline.

So far our January market numbers are strong, but they don't reflect a spirit of broad participation.