In the previous section, we concluded that Amaranth’s
primary trading strategy consisted of a spread trade that was
primarily long winter natural gas contract months and short
non-winter natural gas contract months. Chincarini (2007a,
2007b) noted that such a spread trade had performed well on
average since 1990. That is, a long winter, short non-winter
spread trade in proportion to the open interest on NYMEX
tended to do very well in September. It is not clear whether
the Amaranth natural gas traders actually backtested the
strategy or whether they used experience combined with their
own trader instinct.22 If one backtests the Amaranth strategy
of August 31, 2006 on past years, one finds that the strategy
produced a significantly positive average return of 0.74% per
month or 8.96% on an annualized basis with relatively small
losses in down years (See Figure 6)