After read your thread, I was curios by the idea so decided to look at the correlation. Since I don't have future's data (I never traded futures and currently don't have account set up trading future), so I downloaded index daily closing data from yahoo and found that 180-day crrelation is negative (unfortuanately, I made a couple missteps afterwords, my win98 frozen up so I wasn't able to save result, therefore wasn't able to go back double check it). I was wondering did I do my calculation wrong? or it can happen this way? Was wondering what have you seen.