Post #1271: COVID-19 trend to 9/29/2021, no change

Posted on September 30, 2021


The US Delta wave continues to recede.

The U.S. is now 32% below the 9/1/2021 peak of the Delta wave.  New cases are down 14% in the past week.  We now stand at 35 new COVID-19 cases per 100K per day, down from a revised 35.9 yesterday.

That is mostly being driven by rapid reductions in the states that led the Delta wave on upswing, most notably, Florida.  With 27 new cases / 100K / day, it is now below the U.S. average.

Data source for this and other graphs of new case counts:  Calculated from The New York Times. (2021). Coronavirus (Covid-19) Data in the United States. Retrieved 9/30/2021, from”  The NY Times U.S. tracking page may be found at



Alaska is the sole outlier at this point, and it may have topped out.  If true, once again we get this weird self-limiting aspect of the pandemic.  In any one state, new cases seem to expand right up to the point where hospitals are full.  And then they start to recede.  This is easily the 20th time we’ve seen that same story play out, beginning with New York City at the very start of the pandemic.


North Dakota is the only other state that combines a high current case rate, and a rapid rate of growth in new cases.  That’s only interesting because North Dakota led the way upward on last year’s winter wave.



And here’s where we stand today (red line), compared to last year (blue line).