Finding the absolute maximum date in a column

[sadsmileyface]

I've tried a number of methods to do what I think is a very simple task but I'm not quite getting the result I expected. I have a column of data containing dates, and I just want to know for that range, what is the maximum date in the range? 

I thought that this would work, but it doesnt: Maxdate = CALCULATE(MAX('Availability'[Publishing Date].[Date]))

I expected that it would look at the entireitry of the column and return the absolute maximum date found in that column in each row. Instead, it just returns whatever is the date value of that row- so it's just two columns that are the same as each other. 

Is this perhaps not the correct thing to use?

[Greg_Deckler]

You probably want something like:

Maxdate = CALCULATE(MAX('Availability'[Publishing Date].[Date]),ALL('Availability'))

[sadsmileyface]

Thanks for that- I gave it a shot but it didnt return like I'd hoped.

It returns a date of 31st December 2018, when ideally (since today's date is the most recent occurance in the column) it should be returning a maximum of today's date, 5th December 2018.

[Omega · Accepted solution]

If you are expecting to get the last data from a range of selected dates, then try the below measure/column: 

Last Date = MAX('Availability'[Publishing Date])

But, if you are expecting the last date to be always today's date, then try the below measure/column: 

Last Date = Today ()

[sadsmileyface]

That's it! I used the first one and it worked absolutely perfectly! Thank you!