Thread by @dcpetterson

A tale of two states
Minnesota and South Dakota are adjacent. Both are primarily rural with a couple of denser urban areas. Minnesota 's population is far greater, an estimated 5.6 million, with S. Dakota's at less than one million.

Which is faring better in this pandemic?

1/15

We're told urban density is an important factor encouraging spread. The Minneapolis/St Paul urban area (the red portion on this map) has an estimated 3.5 million people, nearly four times the population of the whole of South Dakota.

2/15

This graph shows how Minnesota is doing compared to the rest of the country. The pinkish line is MN, the green line is the US in total. The graph is logarithmic (look at the scale on the left), which shows the rate of growth well.

3/15

The graph shows the number of confirmed coronavirus cases per 100,000 residents, so it's a number adjusted for population. We'd expect a state with a lower population to have fewer cases, even if the rate of infection is the same. Cases per 100,000 adjusts for that.

4/15

Right now and for some time Minnesota has the lowest infection rate of any state in the nation, despite having a large urban center. That's because the governor instituted closures and stay-at-home orders early. This is what it looks like when the state is on top of things.

5/15

Now let's look at adjacent South Dakota. Instead of having a downward-curving line--which means the rate of increase is slowing--here we see a nearly straight line--which means the number of cases is growing steadily and exponentially.

6/15

Note that South Dakota started out very low--by far, the lowest per-capita rate of infections in the nation. But after less than two weeks, the growth rate began climbing, and has stayed on the same explosive growth ever since.

7/15

As of this writing. MN has 1809 cases. SD, with about 1/6 the population, has 1,311 cases, or nearly 3/4 as many as Minnesota.

The two states are roughly equal in size (MN = 79,610 sq mi of land area, SD = 75,885 sq mi), so MN has nearly six times the average pop density.

8/15

It's clear the difference in performance here is the difference in policy. Kristi Noem, the Republican Governor of South Dakota, has refused to issue any restrictions at all. She is allowing a massive uncontrolled statewide outbreak of the deadly pandemic.

9/15

Look again at what's happening. South Dakota is the only state in the nation where the logarithmic growth is a straight line. The growth for every other state (and the nation as a whole) bends down as states have responded and tried to handle this emergency. Not SD.

10/15

Remember, any change takes at least two weeks to be apparent, as it takes that long for symptoms to appear. The people who will show as new infections two weeks from now are already infected, and nothing anyone does today will affect the growth curve for the rest of April.

11/15

If South Dakota had a total lockdown right now, and stopped all infections today, the growth line would continue on its current course for the rest of this month.

South Dakota cases are growing tenfold about every two weeks.

13/15

If the current growth rate continues, then no matter what Governor Noem does now, by the end of this month South Dakota could have over 10,000 #TrumpVirus cases and would certainly be one of the most serious hotspots in the nation.

14/15

The state has already had one of the biggest single clusters of cases anywhere in the country, forcing the shutdown of one of America's biggest meat processing plants in Sioux Falls.

This is what Republican "governance" does.

15/15

usnews.com/news/best-stat…

PS You can look at your own state (and play with some aspects of how the graph looks) here:
time.com/5814139/corona…