Last updated: 11/25/2020.

Data Geek Alert!
The data presented here should NOT be your sole metric for making decisions about your personal health and safety. Always listen to advice and directives made by Federal, State, and Local health experts!

Open this tab to learn about how we collected and presented this data.

To compile this information, we utilized NYC Department of Health’s public COVID-19 github data accessible via NYC Open Data. Please refer to the readme for this dataset for complete caveats and qualifiers. For compiling Bay Ridge’s COVID history, we used the daily GIT commits for zip code 11209, utilizing the data-by-modzcta.csv dataset.

Please note that this data contains occasional “null” entries, reflecting dates where the city data was not updated.

Additionally, the datasets are always continually cleaned and updated resulting in seemingly odd day-to-day data changes. These instances often reflect hospitals and health agencies updating their data to reflect new information, such as a case being assigned to the wrong zip-code.

Thus, it is important to note that this data is not exact. The data provided should be used to infer general trends only, as represented by our moving 7-day averages.

The data for this visualization is freely downloadable on the Tableau website.

Interpreting This Data…

You’ll notice two elements to each graph: a bar graph, and a line graph. The bars show the daily totals for each statistic. The line shows the 7-day average. Hovering over a specific date will show more details and exact numbers.

In our Daily New Cases graph, the line graph color changes based on whether the average is rising or falling: red for rising, blue for falling.

In our Daily Tests graph, the color of the line becomes warmer the more positive tests were found on that day. This helps to highlight if an increase in testing has been prompted by an increase in positive tests, or another external factor.

Why are there gaps?

This data is collected from the NYC Department of Health, and some days did not see an update to zip-code level data. Other days had data retroactively adjusted for accuracy. The moving 7-day average (line graph) is thus a more accurate indicator of overall trends since it smooths these errors out.

Additionally, individual numbers for testing were not available at a zip-code level before June 10th.

Why is are the daily new cases increasing so steadily?

It is difficult to say! There are three factors we can identify that may be contributing to the increase, which seems to be the beginnings of a second wave:

  1. The ongoing infection rates in hotspots throughout South Brooklyn.
  2. Widespread community spread as cold weather drives people inside (including indoor dining) where aerosol spread is more likely.
  3. A decline in testing combined with a rise in cases, which pushes the % positive rate up on purely mathematical grounds.

This level of infection is the worst we have seen in Bay Ridge since late May, when data was first made publicly available about the virus.

A recent dip in the infection rates near Election Day are due to a series of dates in which the available data was “corrected” by the Department of Health. This means that a few days saw negative numbers of new infections, which reduced the positivity rate. Additionally, the timeframe leading up to Election Day saw record lows of new tests being performed. This may have contributed to a blind spot in the data, where infection rates seemed unusually low. As of now, the infection rate is climbing again.

What’s that big spike in Mid-August?

The mid-August spike, that nearly exceeded a 5% average positivity rate, corresponds to a Sunset Park localized outbreak. City officials later determined that the outbreak was not widespread but centered on specific households and illegal large-gatherings in Sunset Park. However, the city didn’t publicly confirm through contact tracing that any of the large-gathering Karaoke parties (which were raided and shut down) were the source of the outbreak.

Considering that Bay Ridge experienced a COVID-19 spike, it’s doubtful that the August outbreak was solely due to isolated events and households within Sunset Park, as was widely reported.

These spikes should also serve as a strong reminder that localized outbreaks and community spread is a very real possibility, even when overall city numbers appear to be going down.

Is this data useful in determining if local schools are safe?

No.

Our schools are attended by staff and students from many different zip-codes, which this data does not capture. Zip-code level data cannot and should not be used to prove classrooms are safe.