Create burndown chart in Excel using exported reports

Has anyone been able to build a report generated daily that shows number of points of active tasks? These excel spreadsheets would then need to be aggregated and a chart created from the data.

I'm trying to do this retro-actively but as Wrike cannot track the date a task is completed, even when I enter a range it only shows me all the active jobs per the project. 

I would love any script you have that can aggregate these exported reports or any tips in setting up the reports correctly.Additional info: I run in sprints. I have crated a custom category for points and the table mode will total these even. By starting with a daily report, exporting it, and combing all the files, I can make my own burn down. It's just a same I have to do all this work and Wrike still hasn't figured out that this is something we need. 

help.wrike.com/hc/en-us/articles/209604449-Reports-Overview#export