California

Interactive Charts for the State of California

INDEX
  1. Daily Cases, Tests & Positivity Rate
  2. Daily Patients, ICU, HUR & IUR
  3. Daily Fatalities, CFR, IFR
  4. Rt Values & Zorgi Scores
  5. Fatalities, Cases, Patients & Positivity Rate
Daily Cases, Daily Tests & Positivity Rate

Daily cases (the blue column) are a 7 day moving average. Daily tests (the beige area) are also a 7 day moving average. The positivity rate (red line) is derived by dividing the number for daily tests on a given day by the number of cases on the same day:

Tests / Cases = Positivity Rate



Daily Patients, HUR, Daily ICU & IUR

This chart shows the most critical hospital metrics, compiled by the covidproject.com. Bed counts are from the American Hospital Directory and may not be accurate, since they are from before the pandemic.

The Hospital Utilization Rate (HUR) is derived by dividing the number for daily patients into the number of beds for the state. The IUR is derived the same way, except the numerator is the number of ICU beds for the state.

Since the number of beds changes from year to year and even from week to week, the important thing to look at here is the trend, not individual data points.


Daily Fatalities (red area), Case Fatality Rate (blue line), ICU Fatality Ratio (red line)

Daily fatalities are based on a 7 day moving average. The Case Fatality Rate (CFR) is derived by dividing the daily 7 day moving average of fatalities by the daily 7 day moving average of cases from 14 days prior to that day. The actual CFR can’t be reliably stated until the pandemic is over, but most experts believe it will be somewhere less than 1%.

The ICU Fatality Ratio is derived from dividing the daily 7 day moving average of fatalities by the 7 day moving average of daily ICU patients from a week prior. This does NOT mean that this is the actual number of patients from the ICU who die. It simply is a ratio with a bit less lag time than the CFR.


Rt Values & Zorgi Scores

Rt is known as the effective rate of transmission. The initial rate of transmission, R0 (pronounced R not) is the rate for a new disease and a population that has never been exposed to it. Most experts think the R0 of COVID is between 2 and 3.

This means that every person who has COVID on average infects 2 to 3 more people. This may seem like a low number, but it can quickly lead to exponential growth. R0 does not change. It is a fixed number, but its exact value can’t reliably be determined until a pandemic is over.

Rt, the effective rate, changes over time. It is calculated through a model that incorporates cases, case growth, hospitalizations, and a variety of other factors. There are many models of Rt, but the one I use comes from rt.live.

The Zorgi Score is purely an analytical tool I use to figure out which localities I should examine in greater detail. They are not epidemiological ratings. On another page, I have a detailed explanation of how the Zorgi Scores are calculated.


Fatalities, Cases, Patients & Positivity Rate

This is another way of showing the interrelationship between these metrics. Cases and fatalities are all based on 7 day moving averages. Patients are the daily total for that day downloaded from the CA HHS.

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