I wonder if the testing protocol changed. The protocol used to be that, if you walked into a hospital or doctors office with covid symptoms, you were tested. But if they're now testing everyone who walks into the hospital or a doctors office regardless of what their symptoms or ailments are, then that's going to change your percentage of positives. The new guidance recommends that asymptomic people get tested, so it's possible that Maryland changed their protocol. I would expect that, if you expand your protocol to test asymptomatic people, your positivity rate would decrease. I don't think that confirms that the disease prevalence is decreasing though. It just means your protocol changed.