INDIRECT stopped working

I don't know much else to say other than what's in the title to describe the issue.

About my file:
Even in its most basic form (not nested within other functions) it doesn't work; see cell A1. In the picture, all the cells with #REF! worked previously, and they referenced data contained on sheets titled US23, US27, etc. Changes I've made in the file was to remove a data connection (query), and removed around 45,000 rows of data from several of the sheets. The file size was getting large, and thus slow. I was trying to trim it a bit to use the document as a proof of concept.

Other than that, I have no idea what caused this.
Excel1.jpg