Identifying Rising trends in Columns

Short but useless answer -- yes, this sort of thing is possible. After most of a day, I will venture some thoughts.

It isn't clear to me exactly how you determine when they are "trending upward" or "trending downward". I find that a big part of these "signal processing" problems often begins long before I get into the spreadsheet (or whatever programming language I want to use) and think through exactly what I mean by trending up or trending down.

I often find that I start these signal processing problems with a column the tells me something about "change". In this case, it seems that your only interest is whether the change between entries is going up (positive) or going down (negative). I might start solving this problem with a column that tells me when it went up and when it went down. Something like =SIGN(B2-B1) in H2 (copied down). This gives me a column of 1s (indicating increasing trend) and -1s (indicating decreasing trends). Of course, this is just a simple example of the formula that could be used. Often the difficult part of this is deciding exactly what I want in this helper column (how much do I need to smooth the signal before calculating the direction of change or any other complication I need to account for).

From there, "catching" trends means analyzing this helper column to tell me where the trends are. Start/end of trends will be detected as entries where the direction changes sign (changes from 1 to -1 or from -1 to 1), if that's all it means to "catch" a trend. Then create another formula that will perform the exact "catch" operation on the helper column (or additional helper columns, if they will help).

I have no real specific suggestions for this particular example, because I am not sure exactly how you want to identify the trends. I expect the algorithm will include some way of calculating direction of movement, followed by an analysis of those calculations. There may or may not need to be a part of the algorithm that needs to detect the difference between real trends and "signal noise". Help us understand exactly how you want to detect these trends and we'll try to help as best we can to program those algorithms into the spreadsheet.