Creating a Running Total from Counts

Creating a Running Total from Counts

I have a table with the following 3 columns:
Active Users
Terminated Users
Total Users

I was able to calculate 'Total Users' by subtracting the other two. This gives me a monthly net Users for an Organization.

Now I need to generate a 'Users - Running Total'. I know this table can be put into a graph and get the running total but I'm combining this table with several about User usage and need to know a running total of users each month.

I've tried several SQL methods but can't get the running total of users.