Dome Decibel Meter. Have I been living a lie?

I've always found that Decibel thing on screen to be a little dubious. It's been deafening on a 3rd or 4th down & it'll show 84.7---then a few minutes later, coming off a time out with everyone sitting on their hands, you get 126. Still say it's us, KC & Seattle for loudest on any given weekend