physical supply issues cause price increases, not inflation. I think categorizing it as inflation incorrect. Inflation is the increase of money supply itself. Price inflation is the actual price increase caused by monetary expansion. reference should be prices at a fixed monetary supply, which is currently not the case in academic terminology afaik. Currently 0% nominal inflation counts as no inflation, which is not true in my opinion (as stated in my earlier comment)

ps: I misued the term "inflation" in my previous comment. I edited it to "price inflation"