With this program you pick the commodity, the months to plot seasonals for and the number of years to use to make them. Then the seasonal indices are computed using the Link Relative Method as outlined on page 121 of Jack Schwager's book, "Schwager on Futures", (1981), though detrending has not been performed. The chart at the right shows why this is useful. Notice the divergence starting at the beginning of the August seasonal between the June and August seasonals (which are moving downward) and the rest of the seasonals (which are moving upward) with the distance between the two groups increasing. This points to a potential spread opportunity. Though only one cycle is shown here, it is possible to show two cycles of the seasonals so that, for example, the end of the August seasonal could be compared to the beginning of the October seasonal.

1. Pick a commodity and the month(s).

2. Select the chart type. The jpegs are faster; the applets are interactive (zooming in is possible and there are data popups).

3. Select the number of years of data.

4. Select the number of cycles. Use 2 when looking for seasonal divergences (see Using Seasonal Divergences to Find Spread Opportunities). Otherwise use 1.

5. Press "Get Chart". There's a lot of data to download, so be patient.

This is a limited set of commodities available to nonsubscribers. Subscribers can access data for over 40 commodities.