it stopped because has reached 50% of all time heights and lows (from 1953 till now). There are three most important lines when it comes to investing. All time highs, all time lows and average based on this two points. At this moment we are exactly at the mean. It doesn't mean that it will move up and act as a support line, but as an investor (not a trader) as long the price moves up above this line you should short sell and if price moves below you start buying because it means that the currency starts to be cheaper. So if the price is below the line its considered to be cheap and if is above that means its expensive.