Top 9 US States by Positivity Index 9/8/2020
The positivity rate is "the percentage of positive cases among those who are tested". See https://minnesota.cbslocal.com/2020/07/13/what-exactly-does-the-covid-19-positivity-rate-tell-us/ for more information. The following chart is from https://coronavirus.jhu.edu/testing/testing-positivity where its is stated "On May 12, 2020 the World Health Organization (WHO) advised governments that before reopening, rates of positivity in testing (ie, out of all tests conducted, how many came back positive for COVID-19) of should remain at 5% or lower for at least 14 days."
The top 9 states are shown below ranked by Positivity (from https://coronavirus.jhu.edu/testing/testing-positivity 9/8/2020) together with some statistics.
| State | ID | Population | Positivity | Covid-19 confirmed so far | deaths so far | %deaths/ confirmed | confirmed/ MPop so far | deaths/ MPop so far | smoothed (daily Confirmed/ MPop) | smoothed (daily Deaths/ MPop) | Political leaning | Income per capita ($) |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| North Dakota | ND | 756927 | 19.58% | 13872 | 156 | 1.12 | 18326.7343 | 206.0965 | 353.3083 | 2.076064 | Swing | 33071 |
| South Dakota | SD | 858469 | 18.73% | 15403 | 173 | 1.12 | 17942.4068 | 201.5215 | 275.2408 | 0.99845539 | Republican | 26959 |
| Alabama | AL | 4858979 | 18.42% | 133606 | 2277 | 1.7 | 27496.7231 | 468.617 | 176.1099 | 2.263850 | Republican | 23606 |
| Kansas | KS | 2911641 | 18.36% | 56854 | 579 | 1.02 | 19526.4457 | 198.8569 | 224.5175 | 2.5513348 | Republican | 27870 |
| Mississippi | MS | 2992333 | 17.28% | 89069 | 2619 | 2.94 | 29765.738 | 875.2368 | 186.0469 | 4.965070 | Republican | 21036 |
| Iowa | IA | 3123899 | 15.31% | 71142 | 1185 | 1.67 | 22773.4635 | 379.3336 | 236.6091 | 2.7438239 | Swing | 28361 |
| Idaho | ID | 1654930 | 14.78% | 33978 | 389 | 1.14 | 20531.382 | 235.0553 | 140.2735 | 1.8990876 | Republican | 23938 |
| Missouri | MO | 6083672 | 14.5% | 96181 | 1690 | 1.76 | 15809.6952 | 277.7928 | 221.7411 | 3.0057034 | Republican | 26126 |
| Florida | FL | 20271272 | 13.32% | 650092 | 11915 | 1.83 | 32069.6205 | 587.7776 | 134.2646 | 3.8125735 | Swing | 26582 |
The following charts are obtained from the analysis of the JHU data.
| Cumulative confirmed cases | Cumulative deaths |
|---|---|
 |  |
| Covid-19 % deaths/confirmed cases | Covid-19 confirmed cases per million population | Covid-19 deaths per million population |
|---|---|---|
 |  |  |
| Covid-19 smoothed confirmed cases per day per million population | Covid-19 smoothed deaths per day per million population |
|---|---|
 |  |
Observations:
- Florida reported its first cases 3/3/20 and its first death 3/8/20, the same days as the Kansas and Missouri announced their first confirmed cases. None of the other 6 states had any confirmed cases by this date.
- As would be expected since Florida has over three times the population of any of the other states, its confirmed cases and. deaths lead the way by a wide margin.
- In terms of deaths/confirmed cases Missouri led until the end of July when Mississippi took the lead.
- When one normalizes cases by the population of each state, then the confirmed cases and deaths are more evenly spread, and none of the states has flattened its curve of confirmed cases.
- Idaho appears to have managed to flatten its curve of deaths/million population after 5/11/20 until 7/15/20 when it took off again
US States time series plots of Covid-19 cases, May-June
- time series plot of the US Confirmed cases by state on a log scale.
- percent deaths/confirmed cases by state as a function of date:
US States Motion Charts of Covid-19 deaths vs confirmed cases
Cumulative:
- cases with bubbles sized by US state population and colored by per capita income (Jan 28, 2020 - Apr 28, 2000)
- cases per million population with bubbles sized by US state population (May 1, 2020 - Jun 22, 2020)
- cases per million population with bubbles sized by US state population and colored by per capita income (May 1, 2020, Jun 25, 2020)
- cases with bubbles sized by population density of state and colored by per capita income (May 1 2020 - Jun 26, 2020)
- March 1, 2020 - July 20, 2020
Motion Charts with bubbles sized by US state population and colored by per capita income Mar 1, 2020 thru Jul 20
US State population > 10 Million population US State population 6-10 Million population US States 3-6 Million population US States 1.3-3M population 
US by state + DC every 5 days color=income US by state + DC every 4 days color=%Hispanic+Black 
Daily:
- daily cases per million population with bubbles sized by US state population and colored by per capita income (May 1, 2020, Jun 26, 2020)
- cases with bubbles sized by US state population and colored by per capita income (May 1, 2020, Jun 26, 2020)
Observations
- Looking at the total deaths vs cases it is seen that New York (NY), Delaware (DE), Massachusetts (MA), Rhode Island (RI) and Connecticut (CT) lead the pack followed by Maryland (MD), Illinois (IL) and more recently Louisiana (LA) but other states are catching up.
- It is a similar situation when one normalizes the states by their populations.
- When one looks at the new daily confirmed cases/Million state population and deaths/Million state population it is seen to be very variable day-to-day.
- Arizona's increased confirmed cases pulled it away from the pack starting May 14, 2020, and Florida pulled away starting May 24, 2020
- The values of new Confirmed cases/day/Million State population appears to decrease as one moves forward in time beyond May 23 but then to increase again (driven by Arizona) starting June 14, 2020. Maybe this is part of the "opening".
- Comparing the above with the same data but not normalized by state population
- At the start of May there is a noticeable correlation between deaths and confirmed, by the end of June the correlation is much weaker
- At the start of May the deaths and confirmed is dominated by New York (NY), New Jersey (NJ), Illinois (IL), Massachusetts (MA), California (CA) and Maryland (MD). By the end of June California (CA)is still a leader joined by Texas (TX), Florida (FL), Arizona (AZ), and Georgia (GA).
- Looking at the cases with bubbles sized by population density:
- Some states with high population densities such as New York (NY), New Jersey (NJ) and Massachusetts (MA) have high numbers of confirmed cases while others such as Washington DC, Rhode Island (RI), Delaware (DE) have fairly low numbers of confirmed cases.
- In general, the deaths/confirmed cases appear to be falling with time for especially as we get into June. This may be a mixture of increased testing finding more cases as well as more effective treatment.
- Exceptions that are still increasing include: NJ, MA, PA, CT, SD, NH, IL.
- Jul 22 California passes New York in number of confirmed cases (California population ~ 39M, New York population 20M), New York still has roughly four times California's deaths.
Looking at the July 24, 2020 JHU data there is a strong correlation between the total Confirmed case/state population and the % Hispanic + Black of the state's population.
Confirmed cases/population vs % Hispanic & Black (bubble sizes proportional to state's population) Confirmed cases/population vs % Black (bubble sizes proportional to state's population) Deaths/population vs % Hispanic + Black (bubble sizes proportional to state's population) 
As would be expected there is strong correlation between the number of reported confirmed cases and a state's population and a noticeable correlation between the reported deaths and a state's population.
x axis is the state's population, y axis is the reported Confirmed cases on July 27. x axis is the state's population, y axis is the reported deaths on July 27. 
- Confirmed Cases/population
The ten states with the leading confirmed cases/population as of 7/26/2020 were:
State ID confirmed/Pop deaths/Pop Pop-Density(pop/sq-km) Delaware DE 0.026143 0.00143 485.343 Arizona AZ 0.023728 0.000484 60.109 Louisiana LA 0.023032 0.000806 108.109 Florida FL 0.020909 0.000289 378.019 New York NY 0.020799 0.001648 420.061 New Jersey NJ 0.020023 0.001762 1218.114 Mississippi MS 0.01765 0.000502 63.771 District of Columbia DC 0.017524 0.000864 11020.131 Rhode Island RI 0.017253 0.000949 1021.565 Massachusetts MA 0.017019 0.001255 871.08 The lowest ten states were:
State ID confirmed/Pop deaths/Pop Pop-Density(pop/sq-km) Hawaii HI 0.001176 0.000018 222.887 Vermont VT 0.002236 0.000089 67.923 Maine ME 0.002869 0.00009 43.1 West Virginia WV 0.003193 0.000056 76.717 Montana MT 0.003234 0.000045 7.097 Alaska AK 0.003419 0.000027 1.294 Oregon OR 0.004162 0.000072 41.974 Wyoming WY 0.004532 0.000063 6.037 New Hampshire NH 0.004837 0.000307 148.621 Kentucky KY 0.00612 0.000158 112.067 - The number of days from the first confirmed case to the first death was 57 +- 6 days.