COVID-19 deaths in Florida – an explainer

ANALYSIS

BY JON TAYLOR

Each day, the Florida Department of Health issues a COVID-19 press release updating the Covid-19 situation in Florida:

July 26th, 2020: “Today, as reported at 11AM, there are: 9,344 new positive COVID-19 cases (9,259 and 85 non-Florida residents); 77 Florida resident deaths related to COVID-19”

July 27th, 2020: “Today, as reported at 11AM, there are: 8,892 new positive COVID-19 cases (8,854 and 38 non-Florida residents); 77 Florida resident deaths related to COVID-19”

July 28th, 2020: “Today, as reported at 11AM, there are: 9,230 new positive COVID-19 cases (9,169 and 61 non-Florida residents); 186 Florida resident deaths related to COVID-19”

July 29th, 2020: “Today, as reported at 11AM, there are: 9,446 new positive COVID-19 cases (9,384 and 62 non-Florida residents); 216 Florida resident deaths related to COVID-19”

July 30th, 2020: “Today, as reported at 11AM, there are: 9,956 new positive COVID-19 cases (9,854 and 102 non-Florida residents); 253 Florida resident deaths related to COVID-19”

July 31st, 2020: “Today, as reported at 11AM, there are: 9,007 new positive COVID-19 cases (8,925 and 82 non-Florida residents); 257 Florida resident deaths related to COVID-19”

Unfortunately, these daily press releases provide misleading information on deaths related to COVID-19. As of August 3rd, 2020, the highest number of deaths on any day was July 17, 2020 with an official tally of 146. That number is tentative, since the Florida Department of Health (FDOH) adds to the official tally periodically. Which brings us to the next point:

Every day, FDOH provides the number of deaths added to the official Florida Covid-19 Caseline database. On July 31st, FDOH added 257 deaths to the official records, yet only 24 of these deaths occurred on July 30th. The rest of the 257 deaths occurred as far back as May 2nd. Most of the deaths occurred in the month of July, but we won’t know the full tally for a month or even longer, as deaths are reported to the FDOH with significant delays.

What do the data tell us?

Let’s start by looking at the FDOH official “Deaths by Date of Death” file as of July 26th. We keep records of the database in order to track changes in the database over time. FDOH says on its data page that “the Deaths by Day chart shows the total number of Florida residents with confirmed COVID-19 that died on each calendar day (12:00AM – 11:59PM). Caution should be used in interpreting recent trends, as deaths are added as they are reported to the Department.” Readers likely miss the important component of that disclaimer: “deaths are added as they are reported to the Department.”

Each day, FDOH issues a press release updating the public about changes in COVID-19 data for the state of Florida. In the July 27th, 2020 release: “Today, as reported at 11AM, there are: 8,892 new positive COVID-19 cases (8,854 Florida residents and 38 non-Florida residents) and 77 Florida resident deaths related to COVID-19.” Florida added 77 deaths to the official record, and as the graph below shows, they were spread across many different actual dates of death. Calculating which days added deaths is simple. Yesterday’s database is subtracted from today’s database line-by-line to calculate the difference per day. This gives the number of additional deaths reported by actual date of death.

In total, 77 Floridians were identified, but they did not all die on the same day. They did not die within the 24 hours since the last press release. Below, the bar chart shows the difference in July 27th’s data and July 26th’s data.

What does the entire “Deaths by Date of Death” file look like as of July 27th? Let’s use a stacked bar chart to show how those newly identified deaths add to the overall file.

What the graph above shows is how those new deaths “stack” or fill the X-axis as we move forward in time. Download the data by clicking the options menu in the top right of the graph above. Observe the columns in the file. “Date”, “Additional Deaths Reported As of July 27: 77 Total”, and “Deaths as of July 26”. Sum the second column and you’ll see that the total is 77. The file begins on June 1st, 2020 to aid in visualization. FDOH reports the first COVID-19 death on March 5th, 2020.

Now, let’s review what the reported deaths on July 28th looked like. Florida reported an additional 186 deaths, but again, not all of the reported deaths occurred on the same day, nor did they all occur within 24 hours of July 28th, as the graph below clearly demonstrates.

Here’s how the “Deaths by Date of Death” file looks as of July 28th using the stacked bar chart below. Now, you can identify the deaths added to the file by their respective date of death.

Again, let’s move forward one day in time, and check how the reported deaths as of July 29th are distributed through time in the bar chart below. Florida reported an additional 216 deaths, a “pandemic record” according to the media. Did they all die within 24 hours of each other? No. Did they all die within 24 hours of July 29th? No.

Here’s how July 29th’s reported deaths contributed to the “Deaths by Date of Death” file on that day in the stacked bar chart below.

Thursday July 30th and Friday July 31st were the highest reported additional deaths by a wide margin. However, they did not all die on the same day and they did not all die within 48 hours of July 31st. In fact, over the 7 days from July 24th to July 30th, 538 deaths were identified on those days as their actual date of death, nearly half the total reported by the media. These totals are not final. You’ve already seen very clearly how a delay in reporting exists. While deaths have risen to a troubling rate, the media is not reporting this information correctly.

Below, a stacked bar chart identifies the five reporting days (July 27th, July 28th, July 29th, July 30th, and July 31st) reported widely by the media according to the actual date of death for those reported deaths. Not all of the deaths occurred in the same 5 days. Download the data for yourself so that you can see how the reported deaths are distributed through time.

Below, a stacked bar chart shows how each day’s reported deaths are added to the “Deaths by Date of Death” file as of July 31st, 2020. Reported deaths do not mean that all of those deaths occurred the day prior.

Reported deaths do not mean that all of those deaths occurred the day prior. Journalists, local elected officials, business executives and parents would be well served if the FDOH press release included clarification about the additional deaths reported by graphing the reported total by actual date of death. Each day’s press release is not the sum of people who died since the last press release, as this data explainer demonstrates.

Why is this arrangement of the data in this manner important? First, having a lag in data reporting of deaths, which is the current method of reporting, leads to spikes in the number of deaths reported on any given day. From an economic point of view, this leads to uncertainty that leads risk averse individuals, which most of us are, to overestimate negative effects (such as deaths) and underestimate positive effects (such as lower positivity rates). That is, the current data reporting methodology, which allows for reporting of deaths by date in clumps, could easily lead to erroneous conclusions on the part of economic policy makers. Second, future research on the pandemic will need to sort the data in the same manner as we have to accurately show deaths by date so as to better estimate Case Fatality Rates and other statistics concerning the pandemic.

Below, a stacked bar chart current through August 3rd, 2020 shows how each day’s reported deaths are added to the “Deaths by Date of Death” file.

Jon Taylor is a third-year PhD student in Finance at Florida Atlantic University.