The adjacent chart shows price movement of NCDEX soya oil August contract. From the high of Rs.616.6, soya oil has been heading towards south. On the occasions of minor degree bounces it has been facing resistance near the key day moving averages. Recently it faced resistance there and has started falling down. The fall is breaking up into lower degree waves. The medium term momentum indicator is in line with the fall, whereas the daily momentum indicator has triggered a fresh bearish crossover. Thus unless the level of Rs.583 is crossed the agri-commodity is expected to trade with downward bias. The key levels on the downside will be Rs.566.80 and Rs.555.50.