> It works, but Org does not include variable assignments to exported code
> by default. See org-babel-exp-code-template. The assignment would be
> done if you execute the blocks though.

So I have to set this variable to true?

> Note that year will have a value of "2019\n" with trailing newline.

hm this is unfortunate...

> Yet another approach is including common :var year=2009 header arg.

what do you mean by common? I want to have a report for the years 
2019-2022 for example.