My previously published estimate for U.S. Covid deaths in August was off from the actual number, off by less than one percent.
The total U.S. deaths from Covid-19 for the 4 months of Sept, Oct, Nov, and Dec. based on my analysis of the seasonality of the disease: 376,808 deaths. Add to that number the 187,736 deaths from Feb 29th, the day of the first U.S. death to the end of August, and the total death toll would be 564,544 U.S. total death toll from Covid-19 in 2020. I could be off in this prediction by tens of thousands in either direction.
For 2017, the number of persons in the U.S. who died from Heart disease was 647,457, and from cancer was 599,108. So the number 564,544 makes Covid-19 the third leading cause of death for 2020. however, that assumes the 2020 numbers for heart disease and cancer will be the same as in 2020. In all likelihood, Covid has influenced those numbers. Cancer is probably higher this year, as people have been afraid to go to the doctor or hospital; treatment is reduced, resulting in higher deaths.
The above estimate for U.S. Covid-19 cases and deaths is the low end of the possibilities. Comparison of Covid data from the last several months with studies on seasonality of coronaviruses produces some estimates as high as 1 million or more dead, per month, just in the U.S. from Covid-19, in two or more winter months.