Apparently, and this kind of stands to reason, the use of profanity by CEOs varies with economic conditions.
Bloomberg actually went through and did a word search of earnings call transcripts for the past 10 years. Profanity peaked in 2010, dipped a bit, shot up again in 2012 and has been declining ever since.
I know you want to know what the words are, but I really need my job.
There's a chart that'll give you the details, though: