50% marked on the chart is the retracement form the last 7 months downtrend started at the begging of the January last year. I see here incomplete head and shoulders pattern which may or may not appear in next couple of months.
the top of the formation is in 50% area combined with psychological level which is 20.
one arm is bounced from GAP combined with another 61.8% Fibonacci magic number
Head shoulders formation is very reliable when it is suggesting that the trend will continue see link below.
It is worth in my opinion to wait for this pattern to appear and when it will we can get very nice risk reward ratio for short position.