Most people don't look at simple Line charts CEOChair, the traders who trade based on charts will use open/high/low/close charts like Candles.
In that you can clearly see the recent high volume day with a intra-day high of 83cents. High volume days are important as that represents a time when a lot of shares traded hands.
Remember, resistance isn't a simple line. It covers an area so it is never simply 80 cents or 83 cents, there will be resistance along the whole range. Usually when people quote a number it is the centrepoint of that resistance (or sometimes the start), rarely is it the end.
SXY Price at posting:
80.0¢ Sentiment: Hold Disclosure: Held