Previous month based on largest value in data

[slamanager]

Hi,

Im building a matrix/grid to display 13 months of data with the months displayed accross the top.

Im using the LARGE function to determine the "latest" date in my data and then im trying to calc the previous months from this date. After working on other parts of the grid i just noticed that i have a repeating month ???

Summary sheet cell D4
=LARGE(DATA!$E$7:$E$10000,1) looks on the data sheet in Col E for the "latest" date.
Summary sheet cell E4
=DATE(YEAR(D4),MONTH(D4)-1,DAY(D4))
and then i drag this formula to the right to show 13 months but i get two MARCH months ??

What would be the answer to my plight, please.

 

[slamanager]

found an answer

=DATE(YEAR(D4),MONTH(D4),0)