There are several national-level aggregations of county-level COVID case and death data that researchers have to choose from. Each source has its own data collection methods, which can result in variations in numbers across sources.
On this page, we explore to what extent the following two data sources for county-level cumulative counts of confirmed COVID-19 cases and deaths are comparable. In our comparison, we focus on cumulative case counts as of 8/31/2020 (data accessed on 9/01/2020).
New York Times (NYT): The New York times keeps maintains a data set reporting daily cumulative counts of COVID-19 cases and deaths.
USAFacts: USAFacts also maintains a data set reporting daily cumulative counts of COVID-19 cases and deaths.
The data for each of the two sources are gathered from state and local public health agencies, however there are some differences between the two sources in how the data is reported. This blog post reviews some of the major differences, for example:
Time of update: NYT is updated once daily around 8am EDT with case and death counts from the previous day. USAFacts is updated once daily around 12am PDT (3am EDT) for cases from the previous day. Because USAFacts is updated before NYT, USAFacts generally reports lower case and death counts than NYT for a given day.
Geographic exceptions: NYT reports cases for all five boroughs of New York city as a single area (“New York City”). USAFacts reports New York City cases separately for all five counties, though also has a category for “New York City Unallocated/Probable”. NYT reports all case for Kansas City in a single group (“Kansas City”). The case counts for the four counties that include parts of Kansas City represent only the parts of the counties that are outside of Kansas City. In the USAFacts data, all Kansas City cases are allocated to Jackson County.
Other differences: See the blog post linked above for more information on the differences between the data sources.
Date updated: 8/31/2020 (data downloaded: 9/01/2020)
The following plot shows daily cumulative case counts for each of the two data sources, as well as the difference in case counts (NYT-USAFacts) and percentage difference in case counts (NYT-USAFacts)/USAFacts over time.
The case counts reported in the two sources are similar, and have gotten more similar in the past couple months. During the month of August, NYT consistently reported approximately 0.6% more cases than USAFacts, compared to a difference of 1% throughout May and June.
The following plot shows daily cumulative death counts for each of the two data sources, as well as the difference in death counts (NYT-USAFacts) and percentage difference in death counts (NYT-USAFacts)/USAFacts over time.
While the death counts reported in the two sources are similar. NYT has tends to report about 1% more cases than USAFacts. The difference in death counts between the two sources has stayed relatively steady since early May.
Date updated: 8/31/2020 (data downloaded: 9/01/2020)
This plot shows only states where there are unallocated cases or deaths in either data source.
USAFacts reports around 19,000 cumulative cases in Georgia that are not attributed to any county, compared to only 2,500 such cases in NYT. Correspondingly, USAFacts reports approximately 16,500 more cases for the state of Georgia compared to USAFacts (the two data sources report similar numbers of cases for each county in Georgia).
| source | cases |
|---|---|
| NYT | 251768 |
| USAFacts | 251768 |
There are currently only a handful of such deaths, and no such cases
| County | State | Cases | Deaths |
|---|---|---|---|
| New York City Unallocated/Probable | NY | 0 | 21 |
Date updated: 8/31/2020 (data downloaded: 9/01/2020)
All county FIPS codes from the New York Times data are in the USAFacts data with the exception of FIPS codes corresponding to counties in Puerto Rico or other U.S. territories.
| State | # Counties in NYT but missing from USAFacts |
|---|---|
| Northern Mariana Islands | 2 |
| Puerto Rico | 78 |
| Virgin Islands | 3 |
There are a few FIPs codes that appear in the USAFacts data but not in the NYT:
USAFacts has rows for each of five counties in New York City, whereas NYT has a single row for New York City
The Grand Princess cruise ship is included in USAFacts but not in NYT
USAFacts has a row for Hoonah-Angoon Census Area, while NYT does not
| State | County | FIPS | Cummulative cases | Earliest date | Latest date |
|---|---|---|---|---|---|
| AK | Hoonah-Angoon Census Area | 02105 | 18 | 2020-07-24 | 2020-08-31 |
| CA | Grand Princess Cruise Ship | 06000 | 21 | 2020-03-07 | 2020-08-31 |
| NY | Bronx County | 36005 | 51610 | 2020-03-08 | 2020-08-31 |
| NY | Kings County | 36047 | 64998 | 2020-03-05 | 2020-08-31 |
| NY | New York County | 36061 | 32119 | 2020-03-02 | 2020-08-31 |
| NY | Queens County | 36081 | 70222 | 2020-03-07 | 2020-08-31 |
| NY | Richmond County | 36085 | 15288 | 2020-03-09 | 2020-08-31 |
Date updated: 8/31/2020 (data downloaded: 9/01/2020)
Percentage difference is defined relative to USAFacts ([NYT-USAFacts]/USAFacts).
The following table is arranged in descending order of the absolute value of the difference between the two sources.
| State | County USAFacts | FIPS | NYT | USAFacts | Percent difference |
|---|---|---|---|---|---|
| MO | Jackson County (including other portions of Kansas City) | 29095 | 5521 | 14816 | -63% |
| PA | Philadelphia County | 42101 | 33778 | 29057 | 16% |
| TX | Nueces County | 48355 | 18886 | 15055 | 25% |
| TN | Davidson County | 47037 | 25975 | 23474 | 11% |
| TX | Tarrant County | 48439 | 41617 | 39216 | 6% |
| MI | Jackson County | 26075 | 2554 | 827 | 209% |
| KY | Fayette County | 21067 | 5726 | 4188 | 37% |
| TX | Ector County | 48135 | 4241 | 2810 | 51% |
| TX | Tom Green County | 48451 | 3233 | 2037 | 59% |
| TX | Taylor County | 48441 | 2504 | 1317 | 90% |
| NM | Otero County | 35035 | 1120 | 218 | 414% |
| WA | Snohomish County | 53061 | 7085 | 6198 | 14% |
| MI | Branch County | 26023 | 1298 | 483 | 169% |
| MI | Lenawee County | 26091 | 1300 | 570 | 128% |
| MO | Jasper County | 29097 | 1625 | 2353 | -31% |
| WA | Yakima County | 53077 | 11672 | 10948 | 7% |
| WA | Pierce County | 53053 | 7500 | 6794 | 10% |
| TX | Comal County | 48091 | 2969 | 2353 | 26% |
| MI | Muskegon County | 26121 | 1951 | 1339 | 46% |
| IL | St. Clair County | 17163 | 5850 | 5264 | 11% |
| TX | Smith County | 48423 | 3786 | 3207 | 18% |
| MI | Washtenaw County | 26161 | 3425 | 2903 | 18% |
| WI | Racine County | 55101 | 4441 | 4006 | 11% |
| TX | Brazos County | 48041 | 5137 | 4703 | 9% |
| WA | Clark County | 53011 | 2612 | 2183 | 20% |
| TX | Starr County | 48427 | 3153 | 2782 | 13% |
| TN | Knox County | 47093 | 6786 | 6429 | 6% |
| NM | Cibola County | 35006 | 727 | 398 | 83% |
| MI | Lapeer County | 26087 | 843 | 536 | 57% |
| TX | Navarro County | 48349 | 1338 | 1074 | 25% |
| TX | Angelina County | 48005 | 2250 | 2005 | 12% |
| MO | Greene County | 29077 | 3372 | 3158 | 7% |
| IN | Adams County | 18001 | 188 | 385 | -51% |
| TX | Brown County | 48049 | 634 | 470 | 35% |
| WI | Rock County | 55105 | 1848 | 1686 | 10% |
| AK | Kenai Peninsula Borough | 02122 | 568 | 410 | 38% |
| TX | Deaf Smith County | 48117 | 948 | 801 | 18% |
| TX | Gregg County | 48183 | 2001 | 1880 | 6% |
| MI | Luce County | 26095 | 121 | 5 | 2320% |
| TX | Titus County | 48449 | 1454 | 1356 | 7% |
| AK | Aleutians West Census Area | 02016 | 92 | 7 | 1214% |
| AK | City and Borough of Juneau | 02110 | 257 | 175 | 47% |
| WA | Thurston County | 53067 | 1002 | 925 | 8% |
| TX | Polk County | 48373 | 851 | 778 | 9% |
| MO | Cass County | 29037 | 1140 | 1075 | 6% |
| MO | McDonald County | 29119 | 1049 | 988 | 6% |
| NC | Rutherford County | 37161 | 995 | 938 | 6% |
| KS | Atchison County | 20005 | 219 | 166 | 32% |
| MO | Christian County | 29043 | 728 | 675 | 8% |
| ID | Bannock County | 16005 | 671 | 619 | 8% |
| AK | Valdez-Cordova Census Area | 02261 | 121 | 73 | 66% |
| AK | Fairbanks North Star Borough | 02090 | 685 | 640 | 7% |
| NM | Torrance County | 35057 | 107 | 63 | 70% |
| AK | Kodiak Island Borough | 02150 | 57 | 14 | 307% |
| IL | Whiteside County | 17195 | 541 | 507 | 7% |
| IA | Bremer County | 19017 | 331 | 299 | 11% |
| KY | Ohio County | 21183 | 417 | 386 | 8% |
| KY | Henderson County | 21101 | 455 | 424 | 7% |
| NM | Valencia County | 35061 | 541 | 513 | 6% |
| NV | Churchill County | 32001 | 110 | 84 | 31% |
| KS | Grant County | 20067 | 160 | 134 | 19% |
| TX | Zavala County | 48507 | 287 | 261 | 10% |
| MO | Polk County | 29167 | 317 | 291 | 9% |
| MO | Platte County | 29165 | 502 | 477 | 5% |
| KS | Montgomery County | 20125 | 252 | 228 | 10% |
| KY | Meade County | 21163 | 148 | 125 | 18% |
| TX | San Augustine County | 48405 | 213 | 190 | 12% |
| AK | Dillingham Census Area | 02070 | 26 | 5 | 420% |
| KY | Larue County | 21123 | 100 | 83 | 20% |
| KY | Webster County | 21233 | 116 | 99 | 17% |
| AK | Ketchikan Gateway Borough | 02130 | 62 | 46 | 35% |
| KY | Edmonson County | 21061 | 133 | 117 | 14% |
| KS | Pawnee County | 20145 | 187 | 171 | 9% |
| AK | Southeast Fairbanks Census Area | 02240 | 32 | 18 | 78% |
| KY | Hart County | 21099 | 144 | 130 | 11% |
| CA | Inyo County | 06027 | 160 | 174 | -8% |
| KY | Russell County | 21207 | 189 | 175 | 8% |
| AK | Sitka City and Borough | 02220 | 51 | 38 | 34% |
| ID | Power County | 16077 | 132 | 119 | 11% |
| KS | Trego County | 20195 | 24 | 12 | 100% |
| MI | Manistee County | 26101 | 66 | 54 | 22% |
| CA | Mariposa County | 06043 | 73 | 61 | 20% |
| KY | Union County | 21225 | 107 | 95 | 13% |
| KY | Simpson County | 21213 | 219 | 207 | 6% |
| KS | Chase County | 20017 | 76 | 65 | 17% |
| KS | Pottawatomie County | 20149 | 156 | 145 | 8% |
| MI | Otsego County | 26137 | 155 | 144 | 8% |
| KS | Scott County | 20171 | 96 | 86 | 12% |
| KY | Bourbon County | 21017 | 124 | 114 | 9% |
| ID | Butte County | 16023 | 20 | 11 | 82% |
| KS | Stevens County | 20189 | 68 | 59 | 15% |
| KS | Sumner County | 20191 | 129 | 121 | 7% |
| NY | Essex County | 36031 | 137 | 129 | 6% |
| ID | Bear Lake County | 16007 | 37 | 30 | 23% |
| AK | Wrangell City and Borough | 02275 | 17 | 11 | 55% |
| KS | Stafford County | 20185 | 38 | 32 | 19% |
| KS | Pratt County | 20151 | 49 | 43 | 14% |
| AK | Bethel Census Area | 02050 | 65 | 59 | 10% |
| AK | Haines Borough | 02100 | 10 | 5 | 100% |
| AK | Lake and Peninsula Borough | 02164 | 5 | 10 | -50% |
| KS | Graham County | 20065 | 25 | 20 | 25% |
| KS | Russell County | 20167 | 27 | 22 | 23% |
| KS | Meade County | 20119 | 77 | 72 | 7% |
| KY | McCreary County | 21147 | 99 | 94 | 5% |
| AK | Petersburg Census Area | 02195 | 11 | 7 | 57% |
| AK | North Slope Borough | 02185 | 43 | 39 | 10% |
| AK | Nome Census Area | 02180 | 45 | 41 | 10% |
| KY | McLean County | 21149 | 57 | 53 | 8% |
| IA | Keokuk County | 19107 | 64 | 60 | 7% |
| MI | Charlevoix County | 26029 | 76 | 72 | 6% |
| AK | Denali Borough | 02068 | 4 | 1 | 300% |
| ID | Caribou County | 16029 | 43 | 40 | 8% |
| IA | Ida County | 19093 | 43 | 40 | 8% |
| UT | Garfield County | 49017 | 46 | 49 | -6% |
| KS | Phillips County | 20147 | 54 | 51 | 6% |
| AK | Aleutians East Borough | 02013 | 4 | 2 | 100% |
| CA | Modoc County | 06049 | 10 | 12 | -17% |
| UT | Emery County | 49015 | 18 | 16 | 12% |
| UT | Beaver County | 49001 | 33 | 31 | 6% |
| KS | Republic County | 20157 | 38 | 36 | 6% |
| NV | Storey County | 32029 | 7 | 6 | 17% |
| CA | Trinity County | 06105 | 14 | 13 | 8% |
Date updated: 8/31/2020 (data downloaded: 9/01/2020)
Percentage difference is defined relative to USAFacts ([NYT-USAFacts]/USAFacts).
The following table is arranged in descending order of the absolute value of the difference between the two sources.
| State | County USAFacts | FIPS | NYT | USAFacts | Percent difference |
|---|---|---|---|---|---|
| TX | Nueces County | 48355 | 353 | 271 | 30% |
| TX | Webb County | 48479 | 244 | 180 | 36% |
| MO | Jackson County (including other portions of Kansas City) | 29095 | 77 | 132 | -42% |
| PA | Delaware County | 42045 | 773 | 724 | 7% |
| TX | Travis County | 48453 | 385 | 359 | 7% |
| TX | Bowie County | 48037 | 69 | 44 | 57% |
| MI | Branch County | 26023 | 26 | 3 | 767% |
| MI | Jackson County | 26075 | 62 | 40 | 55% |
| MO | Greene County | 29077 | 30 | 10 | 200% |
| MO | Jasper County | 29097 | 15 | 35 | -57% |
| TX | Midland County | 48329 | 69 | 49 | 41% |
| PA | Allegheny County | 42003 | 330 | 313 | 5% |
| KY | Jefferson County | 21111 | 279 | 263 | 6% |
| TX | Val Verde County | 48465 | 89 | 75 | 19% |
| WA | Yakima County | 53077 | 255 | 242 | 5% |
| WA | Pierce County | 53053 | 181 | 169 | 7% |
| WA | Whatcom County | 53073 | 50 | 39 | 28% |
| WA | Snohomish County | 53061 | 220 | 209 | 5% |
| NC | Buncombe County | 37021 | 80 | 70 | 14% |
| MI | Washtenaw County | 26161 | 124 | 115 | 8% |
| TX | Navarro County | 48349 | 25 | 17 | 47% |
| TX | Harrison County | 48203 | 35 | 28 | 25% |
| MI | Lapeer County | 26087 | 42 | 35 | 20% |
| TX | Lubbock County | 48303 | 100 | 93 | 8% |
| TX | Chambers County | 48071 | 11 | 5 | 120% |
| TX | Brown County | 48049 | 26 | 20 | 30% |
| MO | Clay County | 29047 | 37 | 31 | 19% |
| IL | Rock Island County | 17161 | 60 | 54 | 11% |
| MO | Cass County | 29037 | 16 | 11 | 46% |
| NC | Rutherford County | 37161 | 24 | 19 | 26% |
| TX | Rockwall County | 48397 | 26 | 21 | 24% |
| MO | Jefferson County | 29099 | 45 | 40 | 12% |
| MO | Cole County | 29051 | 8 | 4 | 100% |
| WA | Island County | 53029 | 15 | 11 | 36% |
| KY | Campbell County | 21037 | 17 | 13 | 31% |
| MI | Lenawee County | 26091 | 17 | 13 | 31% |
| TX | Randall County | 48381 | 33 | 29 | 14% |
| RI | Washington County | 44009 | 66 | 62 | 6% |
| KY | Casey County | 21045 | 16 | 13 | 23% |
| IL | Sangamon County | 17167 | 40 | 37 | 8% |
| NC | Union County | 37179 | 52 | 49 | 6% |
| RI | Newport County | 44005 | 6 | 4 | 50% |
| WA | Okanogan County | 53047 | 9 | 7 | 29% |
| KY | Christian County | 21047 | 14 | 12 | 17% |
| WA | Chelan County | 53007 | 14 | 12 | 17% |
| WA | Thurston County | 53067 | 15 | 13 | 15% |
| NE | Sarpy County | 31153 | 17 | 15 | 13% |
| WA | Skagit County | 53057 | 24 | 22 | 9% |
| IL | Kendall County | 17093 | 25 | 23 | 9% |
| IA | Harrison County | 19085 | 2 | 1 | 100% |
| MO | Christian County | 29043 | 2 | 1 | 100% |
| AK | Kenai Peninsula Borough | 02122 | 1 | 2 | -50% |
| IA | Carroll County | 19027 | 3 | 2 | 50% |
| MI | Emmet County | 26047 | 3 | 2 | 50% |
| IL | Woodford County | 17203 | 4 | 3 | 33% |
| KY | Henderson County | 21101 | 4 | 3 | 33% |
| IL | Christian County | 17021 | 5 | 4 | 25% |
| ID | Bingham County | 16011 | 6 | 5 | 20% |
| NE | Madison County | 31119 | 6 | 5 | 20% |
| WA | Walla Walla County | 53071 | 6 | 5 | 20% |
| KY | Pulaski County | 21199 | 7 | 6 | 17% |
| MO | Boone County | 29019 | 7 | 6 | 17% |
| KY | Green County | 21087 | 8 | 7 | 14% |
| MO | Cape Girardeau County | 29031 | 8 | 7 | 14% |
| IL | Montgomery County | 17135 | 7 | 8 | -12% |
| IA | Webster County | 19187 | 9 | 8 | 12% |
| IA | Winnebago County | 19189 | 9 | 8 | 12% |
| MO | Pettis County | 29159 | 9 | 8 | 12% |
| WA | Douglas County | 53017 | 9 | 8 | 12% |
| IL | Tazewell County | 17179 | 10 | 9 | 11% |
| WA | Kitsap County | 53035 | 10 | 9 | 11% |
| WI | Fond du Lac County | 55039 | 10 | 9 | 11% |
| ID | Bonneville County | 16019 | 11 | 10 | 10% |
| MO | McDonald County | 29119 | 11 | 10 | 10% |
| MO | Platte County | 29165 | 11 | 10 | 10% |
| KY | Daviess County | 21059 | 12 | 11 | 9% |
| KY | Muhlenberg County | 21177 | 12 | 11 | 9% |
| NE | Hamilton County | 31081 | 13 | 12 | 8% |
| WA | Grant County | 53025 | 14 | 15 | -7% |
| WI | Ozaukee County | 55089 | 19 | 18 | 6% |