The sharp politicization of the coronavirus pandemic has resulted in a slew of stories — including from myself — evaluating how states have fared in combating the virus. The nature of the outbreak, surging and ebbing regionally over the past year, has meant that different states have often been in a better or worse position than others, often as a function of how those states’ governors have chosen to respond to the situation.

With the first anniversary of the first widespread containment efforts at hand, I decided to compare the numbers for four of the most talked-about states over the course of the pandemic: California, Florida, New York and South Dakota.

To make the comparison, I grabbed four sets of data, using the numbers compiled by the COVID Tracking Project — a crowdsourced effort that wound down this week after serving as one of the only consistent sources of data on the pandemic for much of the past 12 months. For each state, I looked at the cumulative number of cases, the seven-day average of new cases, the total number of deaths and the average of new deaths. Instead of simply comparing them to one another after adjusting for population, I instead compared them to the country as a whole.

This is a bit tricky, so let me use an example.

On April 15, the seven-day average of new cases nationally was about 30,000. In New York, it was 11,571; in Florida, 592. Adjusting for population, the national rate was 90.3 cases per million residents, compared to 476 cases per million in New York and 43 cases per million in Florida. So on that day, the New York average was 386 cases per million higher than the country as a whole and Florida was 47 cases lower. New York was doing worse than the country overall and Florida better.

If we do the same calculation for every day, we get a pattern of curves over the course of the year. Here, for example, is how the cumulative population-adjusted case total evolved.

What do we see? Well, first that New York saw an early surge, which we knew. But here, as will often be the case, we should remember the broader context: for the first months of the pandemic, tests to confirm the virus were in limited supply. We also see a big surge in cases in South Dakota that pushed the state above the national cumulative average, where it has stayed.

This is a bit deceptive, though. If South Dakota had a huge spike in cases over a short period, that would keep its cumulative total well above the national level for an extended period.

And that’s essentially what happened. Looking at daily new cases, we see the big surge in South Dakota in late fall. In fact, we see four surges, one for each state: New York’s in spring, Florida’s in summer, South Dakota’s and then California in winter. South Dakota’s population-adjusted spike was by far the largest.

That pattern of cumulative totals remaining worse than the country overall is also visible when looking at cumulative death totals by state. New York stands out here, following the surge in deaths in that state at the outset of the pandemic. Earlier this year, though, South Dakota’s surge in deaths (adjusted for population) pushed its total higher.

The obvious standout there is California, which at no point had a higher population-adjusted death toll than the country overall.

Which isn’t to say that it didn’t have a higher toll on any given day. We know that deaths follow surges in new cases, and so we see four spikes in daily deaths that correlate to the above surges in new cases. Here, though, New York fares the worst, a function of it having been hit hard early — before treatments for the virus were well understood and before the broad deployment of therapeutic treatments.

That South Dakota surged late is worth considering in that respect: Its death toll was severe well after the disease had become better understood.

If we compare each state’s daily performance relative to the country, we see that California was doing better on a per-population basis than the country overall on all four metrics for more than half of the days of the last year. New York’s total cases and total deaths were usually worse than the country’s, but its new cases and deaths were generally better.

This, too, paints an incomplete picture, since it doesn’t distinguish between a day in which a state was one-case-per-million worse than the country and a day on which it was 1,000 cases worse. If we instead look at the average differences between the states and the country over the course of the year, we get a different sense of how the pandemic unfolded.

How states fared relative to the country on a per-population basis

Figures are averages of the difference in the population-adjusted values for the state and the United States overall. Positive numbers indicate an average that was worse than the country as a whole.

California
Florida
New York
South Dakota
Total cases
-188
+274
+241
+1,513
New cases
+5
+1
-3
+107
Total deaths
-206
-45
+629
+5
New deaths
-5
-2
+12
+15

For those looking to make points about the leadership of any of these states, there’s a lot of fodder. The best summary of the data, though, is that the picture that’s offered is complex.