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Data for New York City (recorded by the NYPD) showed 13 deaths in April. While this is not a historically low number (March 2016 saw 11 fatalities for example), when considering seasonality it is the lowest April value going back to at least 2013 (and likely much earlier).
Figure 78: Monthly road traffic accident fatalities in New York City, 2020 compared with the 2014-2019 range. Source
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Another United States city that has timely road accident data is San Francisco. Data are available for each month of 2020, and also a five-year average for 2015-2019 is given for each month (hence why non-integer values appear on the below graph).
Figure 89: Monthly road traffic accident fatalities in San Francisco, 2020 compared with the 2015-2019 average. Source
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