Trend Analysis

[Guest]

I am tracking a variable for different subjects over time. I want to find
the date at which the trend changes, specifically when the lowest value
occurs in a time series before a rise.

I have a table with the following data:

ID Value Date
1 10 1/10/03
1 5 1/10/04
1 1 1/10/05
1 0.5 1/10/06
1 2 3/10/06
2 3 1/10/01
2 1 1/10/02
2 1 3/10/02
2 2 6/10/02.

I want a query that will give the following results:

ID Value Date
1 0.5 1/10/06
2 1 1/10/02

Any ideas how to do this?

 

[Guest]

Create a query, using the fields you are interested in. Go to Design view,
choose the field you want the minimum value from. Right-click, and choose
Totals. The default in the Total row is Group By. You can click on the
arrow in that box, and choose Min. When you go back out to datasheet view,
all of your minimums should be displayed.

 

[Guest]

Sorry, I wrote my question badly, the data actually look like:

I have a table with the following data:

ID Value Date
1 10 1/10/03
1 5 1/10/04
1 1 1/10/05
1 0.5 1/10/06
1 2 3/10/06
1 1 4/10/06
1 0.1 5/10/06
2 3 1/10/01
2 1 1/10/02
2 1 3/10/02
2 2 6/10/02.
2 0.5 6/30/02

THE GLOBAL MINIMUM occurs AFTER a local minimum. I want to find the first
local minimum so that the query still returns:
I want a query that will give the following results:

ID Value Date
1 0.5 1/10/06
2 1 1/10/02

-LDS

 

[Guest]

Sorry, my question wasn't clear because the sample data didn't show the
problem. I need to find the FIRST LOCAL MINIMUM in a time series and NOT the
GLOBAL minimum. The sample data should look like:

ID Value Date
1 10 1/10/03
1 5 1/10/04
1 1 1/10/05
1 0.5 1/10/06
1 2 3/10/06
1 0.25 3/30/06
1 5 4/2/06
2 3 1/10/01
2 1 1/10/02
2 1 3/10/02
2 2 6/10/02.
2 0.5 6/10/03
2 4 5/10/04

I want a query that will still give the first local minimum:

ID Value Date
1 0.5 1/10/06
2 1 1/10/02

Any ideas how to do this?