Hello

It gives a list configured on the following fields:

Item | DataStart | DataEnd

-There is N items and each can have from 1 to n corresponding intervals.
-present Same article is absolutely random times. That may be the first appearance among 2 100 next row, the next row in 2000
-List Can not be sorted, should remain as

It requires a formula (or macro code) to compare the intervals between them at the same article and, if there is any overlap in daily return "Overlay"

Ex.
Item | DataStart | DataFinal
Iti01 27/03/2015 31/03/2015
Iti01 30/03/2015 04/04/2015
Iti01 26/03/2015 27/03/2015

Example for Overlay:
Date of 30/03 and 31/03 on the second interval is found in the first record
Date of 27/03 in the third interval is found in the first record

Thank You