Using the dollar index as a filter, and why it lags

[Amanhasnoname]

Plenty of scalpers keep DXY or a correlated pair open beside the chart they trade, the idea being that a EURUSD long should agree with a falling dollar. It sounds sensible, but the filter has a built-in problem: the index is a basket, and EUR makes up more than half of it. A EURUSD move is partly causing the index move, so the confirmation is circular a good share of the time.

The second issue is timing. The index is calculated from a basket of quotes, and its feed often arrives a beat behind the pair you trade. On a one-minute scalp, a one or two second delay is the difference between confirmation and a stale picture.

Where it does help is as a veto, not a trigger. If EURUSD pushes up while the dollar basket is also pushing up against the move, that divergence is a warning worth respecting. A filter that only blocks trades is safer than one that creates them.

Better yet, test the filter by simply tagging each trade in your journal as agreeing, neutral or disagreeing with the index, then compare results after a hundred trades. Many people find the difference is smaller than expected.

Has a correlated-pair filter ever improved your numbers measurably, or did it just cut trade count?