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On weekends, some of the people in labs, health departments, hospitals, and medical examiner’s offices who do the work of translating individual illnesses and deaths into data points get to go home. On Sundays and Mondays, when weekend COVID-19 data are reported, we see drops in most of the metrics we compile from states, then higher numbers during the rest of the week. Major US holidays act like super-size weekends: For most metrics, we see big drops followed by equally big spikes—neither of which are likely to be accurate measures of what’s actually happening across the country.

Since Christmas, reported cases, tests, and deaths have all declined sharply. Cases and deaths are once again rising, but given that the New Year’s holiday weekend will also cause data disruptions, we aren’t expecting a return to normal reporting until closer to the middle of January.

Of our four top-line metrics, only hospitalization counts remain relatively stable through holiday data disruptions. There’s no responsible way to interpret the other major metrics until holiday backlogs have come and gone, so for this final update of the year, we’re focusing on hospitalizations, which show only mild and transient holiday reporting artifacts.

Across US regions, we see sharply differing hospitalization figures. COVID-19 hospitalizations continue to drop across the entire Midwest. In the West, hospitalizations have been declining across the Mountain West since December 24, but rising down the Pacific Coast and in the Southwest. We see a similarly mixed picture in the Northeast, where five states reported small declines in hospitalizations, and four—including New York—reported increases. Hospitalization increases across the South suggest that many southern states are experiencing worsening outbreaks: Fourteen of the 17 states in the region reported more people hospitalized with COVID-19 today than one week ago.

The country’s four most populous states—CaliforniaFloridaNew York, and Texas—all saw COVID-19 hospitalizations rise in the past seven days. The increases we’re seeing in high-population states have a much greater effect on national numbers than do declines in low-population states.

These week-over-week changes tell only part of the story, however—a 10 percent rise in an area where hospitalizations are low produces a smaller strain on health-care systems than a 10 percent rise in an area where hospitalizations are already very high. In absolute numbers, the South has by far the highest COVID-19 hospitalizations of any region, accounting for almost half the country’s total—but the South is home to more than twice as many people as the Northeast and nearly twice as many as the Midwest.

4 bar charts showing currently hospitalized over time for each US region. Every region save the Midwest is experiencing an increase in COVID-19 hospitalizations.

A view that adjusts for population allows us to understand the severity of each region’s overall situation. Driven by catastrophic hospitalization levels in Southern California, the West has reached 421 COVID-19 hospitalizations per million people, and closing in on the Midwest’s worst-ever per-capita hospitalization rate. The Northeast now has 392 people hospitalized with COVID-19 per million—more than either the Midwest (310 hospitalizations per million) or the South (387 hospitalizations per million).

4 bar charts showing currently hospitalized per million people over time for each US region. Hospitalizations are at record highs in the South and West.

As COVID-19 case and death numbers in the United States continue to oscillate between relatively low and startlingly high numbers because of holiday reporting slowdowns, we suggest that readers remain focused on the relatively stable hospitalization metrics—and on local guidance about how to have a safe and healthy New Year’s holiday. We’ll be back with another update next week as the data backlogs from Christmas and New Year’s Day continue to resolve.