Building a bar chart tracking month-over-month status changes by project

I have been asked to replicate a bar chart previously manually updated in an Excel file, which we are currently developing a Tableau datasource for. Image of the Excel chart is attached here. 

The chart tracks the total count of projects that changed statuses from month to month, but only considers changes between *specific* statuses (certain status changes are considered "status quo" even if a change occurred). 

Buckets should be as follows, roughly: 

'APPROVED', 'REAPPROVAL' status should populate 1 if the status was neither of these in prior month (this indicates the project "opened" in the current month) 

'CLOSED', 'CANCELLED' status should be a -1 if the status was neither of these in the prior month (this indicates the project was "completed" in the current month) 

All other situations, should be 0, at least for now. (There might be a few other specifics here, but I can work those out on my own, if I can get the basic chart built). 

Then, for each given month, the chart would count all of the 1s and create a positive bar of that total number (so if 5 projects have a "1" in September, meaning they were opened in that month, the positive part of the bar would extend up to 5 on the vertical axis); then the portion of the bar that extends below the 0 of the vertical axis would count all of the -1s and create a negative bar of that total (so if 7 projects have a "-1" in September, meaning they were completed in that month, the negative part of the bar would extend down to -7 on the vertical axis). 

I've attached an Excel sample dataset here that has all of the relevant information for this viz. I know it's only two months, but that's all I have, and if I can get September to work vs. August, then I think I can get other months in the future to work too. (If it's absolutely critical I have mock data for more months, let me know).