The US dollar index has been using the 100 day MA as resistance above (see chart above). Today we are making new lows going back to May and is looking to test trend line support at the 80.91 level. The 200 day MA is the next target at 80.689. A break of these support levels opens the door for further selling pressure in the pair. On the topside with the 100 day MA as a ceiling, it becomes the obvious resistance level.