Update on 6-Apr-18: The $USD moved up decisively above its 50dMA (blue line) yesterday at around 90 which was a key resistance. If it can stay above this blue line, it would be a very bullish move for the reserve currency, at least in the short-term and if it can move above its 200dMA (currently around 92.5) and stay above it, it could even form a strong uptrend. This may surprise many people especially if Gold and Silver also start going up at the same time.
So, the key levels to watch are the 50dMA (blue line) and 200dMA (red line) and whether the $USD stays above or below these lines (see chart below). If it falls below the blue line again and stays below it, then the days of the USD as a reserve currency are likely to be numbered !