I was looking at FL demographics yesterday.
The proportion of people under 30 was way higher recently than the overall US proportion.
Since those folks don't die at the same percentage, that might explain the declining death per cases rate.
It's only one state, so I'm broadly extrapolating.
Here in Illinois the death rate is down, but just modestly. Yesterday under 5%, day before 2%. Kind of bobbing up & down.
But positivity rate has averaged 2.7 the last 10 days.
So, less cases but deaths haven't fall by the same %.
I have not researched it, but I haven't read any substantial change in death demographics.
I guess we'll see in another 7-10 days.