I can't claim any first-principles logic for it. I use it because it's standard in finance and accounting, which is usually the audience for SEC filings. It's e

I can't claim any first-principles logic for it. I use it because it's standard in finance and accounting, which is usually the audience for SEC filings. It's everywhere in finance. https://english.stackexchange.com/questions/181917/mixing-use-of-k-for-thousands-and-mm-for-millions https://english.stackexchange.com/questions/181917/mixing-us... has more background.