Count of distinct values between two date ranges

[HKPHOOY]

Hi,

I'm really hoping someone can help me as I've been banging my head against the keyboard for the last few hours and it' starting to hurt!

I've attached the spreadsheet for ease of reference
In summary if you look at the formula on the tab '2018_Tbl' cell b11 I'm almost there but need to be able to filter between two dates (start and end of each month).

I need a formula to count all the distinct project codes on the RAWDATA_2018 Tab column F:F but between the dates on the 2018_tbl (months) and only counting if the value in column AA on the RAWDATA_2018 tab is 1 (exclude zero). I introduced this column as couldn't think of a way to exclude the different cancellation status on et rawdata2018 table column b; wanted to add the reasons to the formula.

Any help would be greatly appreciated.