The x-axis plots the contract months forward. Thus, in this particular exhibit, 1 represents the returns for the October 2006 futures contract during September, 2 represents the returns for the November 2006 contract in September, and so on. One can see from this exhibit the dramatic negative returns of natural gas futures in September, which was as low as -27% for front-month contracts. One can also see that the negative returns were less for non-winter months.