Mathematical Language is not nicely understood by many people. People may well mistakenly use "regular average" when they really want the 'average per 30 days' but that doesn't change the meaning of those conditions, just as people composing about "stationery automobiles" does not change the meaning of "stationery" or https://financefeeds.com/deribit-and-signalplus-launch-300000-trading-competition-to-engage-retail-options-traders/