How does one do an in text citation of an annual report APA style?
This should be straight-forward.
You have a corporate author, as opposed to an individual, for example "Minnesota Power" is your author, not a "John Smith." Your parenthetical reference will always reflect & track back to your reference list - so, you probably will have a citation like (and I am making this up for example's sake ...)
Minnesota Power. (2011). Minnesota Power annual report, 2011. Duluth, MN: Author.
Depending on how your sentence/paragraph is written, you need up to three parts for the parenthetical reference - author, date, and sometimes the page number. A possible parenthetical reference might be as simple as (Minnesota Power, 2011, p. 7).
Use the following CSS library page for an explanation of a parenthetical reference, and examples of how, depending on the way you are writing, to create your parenthetical reference - http://libguides.css.edu/content.php?pid=61826&sid=454619
Good luck with the rest of the semester.