According to the Stock Trader's Almanac, the last 38 up "First Five Days" periods were followed by full-year gains 33 times, for an 86.84% accuracy ratio; and the average gain for these 38 years is just under +14%. Of the five years that didn't "work", four related to war, and one (1994) produced a flat year. The year 2002 was the last one that failed to be properly predictive, as January started the year up +1.1%, but ended nastily with a loss of -23.4%. For those first five days of January that start off in negative territory, which have been 23 in all, they have been followed with 12 up years and 11 down years. As a sidebar, the last two years have been winners, in that the first five days showed a gain, as did the entire year.
In pre-presidential election years (of which we are in now), this indicator has a stellar record. In the last 15 pre-presidential election years, twelve full years followed the direction of the "First Five Days". Realize that the January Barometer (the direction for the whole month), has an even better track record, with 14 of the last 15 full years having followed January's direction.
Now for the good news: the "First Five Days" of January 2011, a pre-election year, have notched a gain. The S&P 500 [SPX] ended the year at 1257.64 and closed out the week at 1271.50, for a gain of +1.10%. Now let's watch to see how the entire month plays out.