I just stumbled on this study of market returns correlated to the Chinese Zodiac.

Here's the abstract:

Throughout history, Chinese zodiac astrology has significantly influenced the way people in that area think, feel, or make daily decisions. In the zodiac calendar, each year is marked by one of twelve symbolic animals and each animal is associated with its own specific traits. Previous literature suggests investors’ mood, attitude, and behavior are influenced by natural events such as cloudy or sunny weather, or lunar cycles. Cultural events such as holidays or religious feasts are also shown to have impact on investing decisions. In this paper we study the stock market returns in different lunar years in the zodiac calendar. We find that Hang Seng’s mean returns are higher in Rat years and both mean and median returns are lower in Snake years. These results are statistically significant despite a small sample size. For S&P 500, only Snake and Rooster years show lower, statistically significant, holding period return. Results are inconclusive for other animal-years or other categorizations in the zodiac astrology.

Read the full paper here to see if it will give you an edge.