Calculated Item based on Aggregate Item

[kargh]

I'm trying to create a graph that shows two values. Item B is the current value, and Item C is the value from 24 hours previous. I've tried several methods but this is my current item setup:

Item A (Aggregate Item): grpsum()
Item B (Calculated Item): last("Item A")
Item C (Calculated Item): last("Item B", 86400)

I expect that Item B would be the actual value of Item A (essentially a copy), and I expect that Item C would be the value of Item B from 1 day earlier.

What I'm getting is Item B is a copy of Item A, and Item C is a copy of Item B (either current value or previous value).

The reason I created Item B is that time period is not supported with last, so I canno't do grpsum("Group",last,86400). Nor can I do grpsum("Group",sum,86400) since that gives me the sum of all values for the last day.

Any suggestions?

[glebs.ivanovskis]

Item C (Calculated Item): last("Item B", 86400)

Shouldn't there be one more comma? Like last("Item B",,1d)? Otherwise Item B and Item C are identical.

[kargh]

Shouldn't there be one more comma? Like last("Item B",,1d)? Otherwise Item B and Item C are identical.

Oh heck... I didn't even realize that was possible. Thanks for the suggestion!