My son has been involved with gathering and reporting on stats for the state of ohio. He said that there are no reporting standards so the format of the data, and when the data comes in, is all over the place. Often, they don't get stats and have to call to pharmacy/hospital/emergency care to get them. Often they simply get a picture of a form filled out in long hand and can't read the data. And, just to be clear, he said rural areas just don't report because they are often one-man shops. Urban areas don't report because they are often overwhelmed or incompetent. So it is common for them to get no report or crazy reports which they have to run down manually. They then adjust the historical data with what they've learned.the numbers can change after they are reported. So even though todays daily positive was reported at 17,834, if you go back and look at May 17 daily positive on this Thursday for instance, it might have been changed to 19,xxx. Hence when you look at the 7 day rolling average, it also changes based on those corrections/additions from the actual reporting on that morning.
By the way, he's been spot on relative to the drop in deaths. I posted on those and believe I was the first based on his input. Back in Feb, he (and I) predicted a 90% drop in deaths by the end of April because those at greatest risk, those over 65 and/or with a comorbidity, would be vaxxed.