Set analysis : sum quantity for current month and year

[EdgarB]

Hello, 

I am a beginner on Qlik Sense. This subject might been discuted elsewhere allready but I haven't seen the answer to my context. 
Here is the formula i am working on : 

Sum({$< DAT_START_SEAS={"$(=Max(DAT_START_SEAS))"},		
       [Requested Order Date]={"= (Year([Requested Order Date]) = year(today()) and Month([Requested Order Date]) = Month(today())) "}
>}[Net Quantity Ordered])

 I need my requested order date to be set by default on today month and year.

However, this formula gives the right answer by is static. I need the requested oredr date to change as soon as I change it in the filter pane.  I don't want to create a bookmark. 

How can I edit my formula ? Do you have any ideas? 

Thank you very much.