It is know, that the first day of the month provides bullish edge. According to Quantifiable edges not all the months are equal. So, I made a test on S&P500 index, from January, 1980 until February, 2010. It is true, March isn’t the best month to run this strategy.
Only 3 months have significant results based on p-values:
“month 5, p-value 0.0399233570186162″
“month 7, p-value 0.0466800163648646″
“month 11, p-value 0.0218919220125013″
p.s. if somebody is interested in R-Language code to repeat this test, then let me know.