NAS100 has seemed to reached an equilibrium range of 15560-15700, and can be correctly said to have been hovering around the range for quiet a while. At the upper-bound of the range, i.e. the key 15700 level, we expect a further move to the downside till the level of 15560 as a next wave within the equilibrium range. However, a break above 15700 would flip the currently held resistance into support, which would invalidate our short bias at the index.