Calculation for Cumulative Schedules and Inventory

[PBI_1107]

Hello Everyone,
I am stuck with a calculation where
There is Current Inventory (2G3GCurrentInv), followed by months and the Schedules that are there for the specific ID's.

I want a Running total which adds the 2G3GCurrentInv along with the months Schedules and give me values something like this :

This table is showing the result like each months Schedules added with the 2G3GCurrentInv, for the next month the currrent value plus the Next months Schedules so and so forth.

Note : There are some ID which have no Schedules for certain Months I also want to be able to return no value for those months.
Any suggestions will be great.

Thank you all for your time and consideration.

Best,
PBI_1107

[PBI_1107]

I used this DAX Query :

and got this Result :

It is adding up the Schedules from the 2g3GCurrentInv, it does not have like a running total. 
It should be like Oct 23 Inv = Sep 23 Inv + Oct Schedules, Nov 23 Inv = Oct Inv + Nov Schedules, Dec 23 Inv = Nov 23 Inv + Schedules, Jan 24 Inv = Dec 23 Inv + Jan Schedules.... and so on and so forth.
Please let me know, 

Thanks,
PBI_1107