Hi all, I am new here :roll: I am writing an expert to highlight the bar if it's LOW is lower than next day's low or next next day's low. So I write the formula like this: L<Ref(L,1) OR L<Ref(L,2) However, I find that this expert is not effective to the second last bar (of whole period) even it's low is lower than the last bar. Seems that the formula becomes invalid when it tries to refer to the bar Ref(L,2) which does not exists. Any idea?

I actually think that wcinvest888 has the logic right, but is using forward references. wcinvest888, think of it like this: on the fourth last bar your code looks two bars ahead (so its looking at the second last bar on the chart) so MS draws a point on the chart the conditions are true; on the third last bar your code looks two bars ahead (so its looking at the very last bar on the chart) so MS draws a point on the chart the conditions are true; on the second last bar your code looks two bars ahead (so its looking one bar past the end of the chart) so the code is invalid, and this is the case for the last bar too! Rethink your 'system' to think in the opposite direction... if you want the low today to be less than the low in two days time, the opposite direction thoughts are, call the bar that was in two days time, today, now the low today must be higher than the low two days ago. Hope this helps. wabbit :D

Sorry, I misunderstood your question. My fault. Try something like this. As Wabbit mentions, it does use forward referencing. [code:1:db3dded62e]L<Ref(L,+1) AND L<Ref(L,+2) AND L<Ref(L,-1) AND L<Ref(L,-2)[/code:1:db3dded62e]