Month diff

[wanass123]

Please assist me in determining how to correct the month difference because it displays incorrect numbers because it is not linked to the year; please demonstrate how to link the date with the year in order to display the correct month difference for previous months. 

Current result : 

Monthidff	Monthname(Payment_date)
-7	Sep-22
-8	Oct-22
-9	Nov-22
-10	Dec-22
1	Jan-23
0	Feb-23

Expected result : 

Monthidff	Monthname(Payment_date)
5	Sep-22
4	Oct-22
3	Nov-22
2	Dec-22
1	Jan-23
0	Feb-23

[E_Røse]

Try this:

= num(month(Date)) -month(today(1))
+12*(year(Date)-year(today(1)))

today(1) returns the date of the function call, while today() returns the date of last reload. You might prefer one over the other. If you want use date of last reload, it is better to create a variable in the load script like this

Let vToday =today();
Let vCurrentMonth = Month(vToday);
Let vCurrentYear = Year(vToday);

and use the follwoing expression:

= num(month(Date)) -vCurrentMonth
+12*(year(Date)-vCurrentYear)

Please like and mark my answer as a solution, if it resolved your issue.

[Gabbar]

As i see here you are going backwards from current month to your month name.
try using this expression:
A:
load *, ((year(latest_date)*12) + num(month(latest_date)))-((year(Date)*12)+num(month(Date))) as MonthiDiff
load *,
MonthStart(Date(Date#(Monthname,'MMM-YY'),'YYYY-MM-DD')) as Date,
monthstart(date(Today(),'YYYY-MM-DD')) as Latest_Date  from (Source);