# US counties by median Air Quality Index (US EPA), 2019

All 1000 values come from U.S. Environmental Protection Agency for 2019, so the places are comparable. 498 counties have no value for that period and are not ranked.

- Indicator id: `aqi_median`
- Unit: index
- Definition: Median of the daily Air Quality Index (AQI) values of a US county over the days of the year with an AQI, from the EPA AirData annual summaries. The daily county AQI is the highest AQI among the monitors and pollutants reported that day (ozone, PM2.5, PM10, carbon monoxide and nitrogen dioxide). Lower is cleaner: 0 to 50 is good, 51 to 100 moderate and above 100 unhealthy for sensitive groups.
- Source: U.S. Environmental Protection Agency, EPA AirData annual AQI by county: median daily AQI (https://aqs.epa.gov/aqsweb/airdata/download_files.html#Annual)
- Publisher page: https://invokely.ai/en/publishers/environmental-protection-agency
- Retrieved: 2026-10-12
- Citation: U.S. Environmental Protection Agency, Air Quality System, AirData. EPA AirData annual AQI by county: median daily AQI. https://aqs.epa.gov/aqsweb/airdata/download_files.html#Annual. Retrieved 2026-10-12.
- Web page: https://invokely.ai/rankings/median-air-quality-index/us-counties

| Rank | Place | index |
|---:|---|---:|
| 1 | San Bernardino County | 81 |
| 2 | Riverside County | 77 |
| 3 | Los Angeles County | 72 |
| 4 | Kern County | 69 |
| 5 | Maricopa County | 67 |
| 5 | Tulare County | 67 |
| 7 | San Diego County | 66 |
| 8 | Fresno County | 63 |
| 8 | Pinal County | 63 |
| 10 | Imperial County | 61 |
| 11 | Allegheny County | 59 |
| 12 | Clark County | 58 |
| 12 | Cook County | 58 |
| 12 | Jefferson County | 58 |
| 12 | Kings County | 58 |
| 12 | Marion County | 58 |
| 12 | Salt Lake County | 58 |
| 12 | Wayne County | 58 |
| 19 | El Paso County | 57 |
| 19 | Hamilton County | 57 |
| 19 | Montgomery County | 57 |
| 22 | Cuyahoga County | 56 |
| 22 | Harris County | 56 |
| 24 | Bernalillo County | 55 |
| 24 | Bexar County | 55 |
| 24 | Fulton County | 55 |
| 24 | Madison County | 55 |
| 28 | Denver County | 54 |
| 28 | Doña Ana County | 54 |
| 28 | Floyd County | 54 |
| 28 | Jefferson County | 54 |
| 28 | St. Louis city | 54 |
| 28 | Uintah County | 54 |
| 34 | Bergen County | 53 |
| 34 | Calcasieu Parish | 53 |
| 34 | Clark County | 53 |
| 34 | Franklin County | 53 |
| 34 | Henderson County | 53 |
| 34 | Jefferson County | 53 |
| 34 | Orange County | 53 |
| 34 | Pulaski County | 53 |
| 34 | Wake County | 53 |
| 34 | Weld County | 53 |
| 44 | Cameron County | 52 |
| 44 | Clarke County | 52 |
| 44 | Cleveland County | 52 |
| 44 | Dallas County | 52 |
| 44 | Davidson County | 52 |
| 44 | DeKalb County | 52 |
| 44 | Dougherty County | 52 |
| 44 | Gwinnett County | 52 |
| 44 | Hinds County | 52 |
| 44 | Lake County | 52 |
| 44 | Lancaster County | 52 |
| 44 | Madera County | 52 |
| 44 | McHenry County | 52 |
| 44 | Mecklenburg County | 52 |
| 44 | Missoula County | 52 |
| 44 | Mobile County | 52 |
| 44 | Montgomery County | 52 |
| 44 | Oklahoma County | 52 |
| 44 | Richmond County | 52 |
| 44 | Sacramento County | 52 |
| 44 | Scott County | 52 |
| 44 | Shelby County | 52 |
| 44 | St. Bernard Parish | 52 |
| 44 | Stanislaus County | 52 |
| 44 | Stark County | 52 |
| 44 | Travis County | 52 |
| 44 | Union County | 52 |
| 44 | Vigo County | 52 |
| 72 | Bowie County | 51 |
| 72 | Butte County | 51 |
| 72 | Camden County | 51 |
| 72 | Cumberland County | 51 |
| 72 | Delaware County | 51 |
| 72 | Duval County | 51 |
| 72 | Forsyth County | 51 |
| 72 | Hamilton County | 51 |
| 72 | Houston County | 51 |
| 72 | Lafourche Parish | 51 |
| 72 | Macon County | 51 |
| 72 | Merced County | 51 |
| 72 | Tarrant County | 51 |
| 72 | Ventura County | 51 |
| 72 | Washington County | 51 |
| 72 | Will County | 51 |
| 72 | Yakima County | 51 |
| 89 | Adams County | 50 |
| 89 | Alameda County | 50 |
| 89 | Beaver County | 50 |
| 89 | Boulder County | 50 |
| 89 | Chaffee County | 50 |
| 89 | East Baton Rouge Parish | 50 |
| 89 | Garland County | 50 |
| 89 | Hidalgo County | 50 |
| 89 | Larimer County | 50 |
| 89 | Mariposa County | 50 |
| 89 | McCracken County | 50 |
| 89 | Park County | 50 |
| 89 | Tulsa County | 50 |
| 89 | Webb County | 50 |
| 103 | Allen County | 49 |
| 103 | Benewah County | 49 |
| 103 | Bolivar County | 49 |
| 103 | Centre County | 49 |
| 103 | Clinton County | 49 |
| 103 | District of Columbia | 49 |
| 103 | Fairfax County | 49 |
| 103 | Hall County | 49 |
| 103 | Hennepin County | 49 |
| 103 | Hillsborough County | 49 |
| 103 | Jackson County | 49 |
| 103 | Jefferson County | 49 |
| 103 | Madison County | 49 |
| 103 | McLean County | 49 |
| 103 | Nueces County | 49 |
| 103 | Philadelphia County | 49 |
| 103 | Pima County | 49 |
| 103 | Placer County | 49 |
| 103 | San Juan County | 49 |
| 103 | San Luis Obispo County | 49 |
| 103 | St. Louis County | 49 |
| 103 | Walker County | 49 |
| 103 | Winnebago County | 49 |
| 126 | Clayton County | 48 |
| 126 | Duchesne County | 48 |
| 126 | DuPage County | 48 |
| 126 | Garfield County | 48 |
| 126 | Gila County | 48 |
| 126 | King County | 48 |
| 126 | Lea County | 48 |
| 126 | Lincoln County | 48 |
| 126 | Livingston Parish | 48 |
| 126 | Preble County | 48 |
| 126 | Russell County | 48 |
| 126 | Santa Clara County | 48 |
| 126 | Summit County | 48 |
| 126 | Sutter County | 48 |
| 126 | Utah County | 48 |
| 126 | Washington County | 48 |
| 126 | Washoe County | 48 |
| 143 | Albany County | 47 |
| 143 | Arapahoe County | 47 |
| 143 | Benton County | 47 |
| 143 | Broward County | 47 |
| 143 | Clear Creek County | 47 |
| 143 | Comanche County | 47 |
| 143 | Crittenden County | 47 |
| 143 | Cumberland County | 47 |
| 143 | Davidson County | 47 |
| 143 | Douglas County | 47 |
| 143 | Durham County | 47 |
| 143 | Eddy County | 47 |
| 143 | Essex County | 47 |
| 143 | Hamilton County | 47 |
| 143 | Hamilton County | 47 |
| 143 | Harrison County | 47 |
| 143 | Holmes County | 47 |
| 143 | Hudson County | 47 |
| 143 | Inyo County | 47 |
| 143 | Kay County | 47 |
| 143 | Lowndes County | 47 |
| 143 | Madison County | 47 |
| 143 | Mesa County | 47 |
| 143 | Milwaukee County | 47 |
| 143 | Muscogee County | 47 |
| 143 | New Castle County | 47 |
| 143 | Pinellas County | 47 |
| 143 | Rio Blanco County | 47 |
| 143 | San Joaquin County | 47 |
| 143 | St. Clair County | 47 |
| 143 | Warren County | 47 |
| 143 | West Baton Rouge Parish | 47 |
| 143 | York County | 47 |
| 143 | Yuma County | 47 |
| 177 | Baltimore city | 46 |
| 177 | Baltimore County | 46 |
| 177 | Bibb County | 46 |
| 177 | Blair County | 46 |
| 177 | Blount County | 46 |
| 177 | Bronx County | 46 |
| 177 | Cache County | 46 |
| 177 | Carbon County | 46 |
| 177 | Carter County | 46 |
| 177 | Chatham County | 46 |
| 177 | Chester County | 46 |
| 177 | Cochise County | 46 |
| 177 | Columbia County | 46 |
| 177 | Daviess County | 46 |
| 177 | DeSoto County | 46 |
| 177 | Edmonson County | 46 |
| 177 | El Paso County | 46 |
| 177 | Fayette County | 46 |
| 177 | Forrest County | 46 |
| 177 | Greenville County | 46 |
| 177 | Gunnison County | 46 |
| 177 | Jackson County | 46 |
| 177 | Jefferson County | 46 |
| 177 | Jersey County | 46 |
| 177 | Johnson County | 46 |
| 177 | Johnston County | 46 |
| 177 | Knox County | 46 |
| 177 | Lafayette Parish | 46 |
| 177 | Lebanon County | 46 |
| 177 | Leon County | 46 |
| 177 | Mahoning County | 46 |
| 177 | Marshall County | 46 |
| 177 | Montezuma County | 46 |
| 177 | New York County | 46 |
| 177 | Pittsburg County | 46 |
| 177 | Providence County | 46 |
| 177 | St. Joseph County | 46 |
| 177 | Sublette County | 46 |
| 177 | Suffolk County | 46 |
| 177 | Sweetwater County | 46 |
| 177 | Union County | 46 |
| 177 | Vanderburgh County | 46 |
| 219 | Adams County | 45 |
| 219 | Anne Arundel County | 45 |
| 219 | Bell County | 45 |
| 219 | Cambria County | 45 |
| 219 | Champaign County | 45 |
| 219 | Clark County | 45 |
| 219 | Coconino County | 45 |
| 219 | Davis County | 45 |
| 219 | Fremont County | 45 |
| 219 | Gilpin County | 45 |
| 219 | Grand County | 45 |
| 219 | Harford County | 45 |
| 219 | Haywood County | 45 |
| 219 | Jackson County | 45 |
| 219 | Mercer County | 45 |
| 219 | Morgan County | 45 |
| 219 | Neosho County | 45 |
| 219 | Nevada County | 45 |
| 219 | Nowata County | 45 |
| 219 | Ottawa County | 45 |
| 219 | Prince George's County | 45 |
| 219 | Queens County | 45 |
| 219 | Rock Island County | 45 |
| 219 | San Miguel County | 45 |
| 219 | Sangamon County | 45 |
| 219 | Santa Barbara County | 45 |
| 219 | Shawnee County | 45 |
| 219 | Solano County | 45 |
| 219 | Spartanburg County | 45 |
| 219 | Union County | 45 |
| 219 | Washington County | 45 |
| 219 | Waukesha County | 45 |
| 219 | Worcester County | 45 |
| 219 | Yancey County | 45 |
| 253 | Allen County | 44 |
| 253 | Anderson County | 44 |
| 253 | Bartholomew County | 44 |
| 253 | Bay County | 44 |
| 253 | Berks County | 44 |
| 253 | Boise County | 44 |
| 253 | Boyd County | 44 |
| 253 | Butler County | 44 |
| 253 | Campbell County | 44 |
| 253 | Carson City | 44 |
| 253 | Catawba County | 44 |
| 253 | Cedar County | 44 |
| 253 | Clermont County | 44 |
| 253 | Cobb County | 44 |
| 253 | Cumberland County | 44 |
| 253 | Cumberland County | 44 |
| 253 | Dauphin County | 44 |
| 253 | Denton County | 44 |
| 253 | Dewey County | 44 |
| 253 | Ellis County | 44 |
| 253 | Escambia County | 44 |
| 253 | Etowah County | 44 |
| 253 | Fairbanks North Star Borough | 44 |
| 253 | Frederick County | 44 |
| 253 | Graham County | 44 |
| 253 | Granville County | 44 |
| 253 | Guilford County | 44 |
| 253 | Hamilton County | 44 |
| 253 | Hardin County | 44 |
| 253 | Harney County | 44 |
| 253 | Harrison County | 44 |
| 253 | Howard County | 44 |
| 253 | Idaho County | 44 |
| 253 | Jefferson County | 44 |
| 253 | Kanawha County | 44 |
| 253 | Kenosha County | 44 |
| 253 | Kent County | 44 |
| 253 | La Paz County | 44 |
| 253 | La Plata County | 44 |
| 253 | Lane County | 44 |
| 253 | Lenawee County | 44 |
| 253 | Lexington County | 44 |
| 253 | Lincoln County | 44 |
| 253 | Lucas County | 44 |
| 253 | Marion County | 44 |
| 253 | Medina County | 44 |
| 253 | Mercer County | 44 |
| 253 | Miami-Dade County | 44 |
| 253 | Montgomery County | 44 |
| 253 | Montgomery County | 44 |
| 253 | Navajo County | 44 |
| 253 | Northampton County | 44 |
| 253 | Orange County | 44 |
| 253 | Palo Alto County | 44 |
| 253 | Peoria County | 44 |
| 253 | Perry County | 44 |
| 253 | Person County | 44 |
| 253 | Pickens County | 44 |
| 253 | Pierce County | 44 |
| 253 | Porter County | 44 |
| 253 | Rockingham County | 44 |
| 253 | Rowan County | 44 |
| 253 | San Juan County | 44 |
| 253 | Sandoval County | 44 |
| 253 | Santa Fe County | 44 |
| 253 | Santa Rosa County | 44 |
| 253 | Sevier County | 44 |
| 253 | Sullivan County | 44 |
| 253 | Sumner County | 44 |
| 253 | Sussex County | 44 |
| 253 | Teton County | 44 |
| 253 | Tooele County | 44 |
| 253 | Trumbull County | 44 |
| 253 | Uinta County | 44 |
| 253 | Valencia County | 44 |
| 253 | Warren County | 44 |
| 253 | Washtenaw County | 44 |
| 253 | Weber County | 44 |
| 253 | White Pine County | 44 |
| 253 | York County | 44 |
| 333 | Armstrong County | 43 |
| 333 | Ashley County | 43 |
| 333 | Bristol County | 43 |
| 333 | Brookings County | 43 |
| 333 | Calaveras County | 43 |
| 333 | Carbon County | 43 |
| 333 | Carroll County | 43 |
| 333 | Chippewa County | 43 |
| 333 | Clay County | 43 |
| 333 | Clinton County | 43 |
| 333 | Contra Costa County | 43 |
| 333 | Dane County | 43 |
| 333 | Dorchester County | 43 |
| 333 | Dubois County | 43 |
| 333 | Edgefield County | 43 |
| 333 | El Dorado County | 43 |
| 333 | Erie County | 43 |
| 333 | Galveston County | 43 |
| 333 | Greene County | 43 |
| 333 | Hampden County | 43 |
| 333 | Hancock County | 43 |
| 333 | Henry County | 43 |
| 333 | Hunterdon County | 43 |
| 333 | Iron County | 43 |
| 333 | Jessamine County | 43 |
| 333 | Kalamazoo County | 43 |
| 333 | Laramie County | 43 |
| 333 | Lawrence County | 43 |
| 333 | Lehigh County | 43 |
| 333 | Lewis and Clark County | 43 |
| 333 | Linn County | 43 |
| 333 | Loudon County | 43 |
| 333 | Middlesex County | 43 |
| 333 | Monroe County | 43 |
| 333 | Northampton County | 43 |
| 333 | Randolph County | 43 |
| 333 | Richmond city | 43 |
| 333 | Rio Arriba County | 43 |
| 333 | Rockdale County | 43 |
| 333 | Sarasota County | 43 |
| 333 | Suffolk County | 43 |
| 333 | Tehama County | 43 |
| 333 | Tippecanoe County | 43 |
| 333 | Tuolumne County | 43 |
| 333 | Whitley County | 43 |
| 333 | Wyandotte County | 43 |
| 333 | Yavapai County | 43 |
| 333 | Yolo County | 43 |
| 381 | Anderson County | 42 |
| 381 | Atlantic County | 42 |
| 381 | Brewster County | 42 |
| 381 | Buchanan County | 42 |
| 381 | Buncombe County | 42 |
| 381 | Caldwell County | 42 |
| 381 | Cass County | 42 |
| 381 | Cecil County | 42 |
| 381 | Charleston County | 42 |
| 381 | Clinton County | 42 |
| 381 | Dodge County | 42 |
| 381 | Douglas County | 42 |
| 381 | Essex County | 42 |
| 381 | Fayette County | 42 |
| 381 | Frederick County | 42 |
| 381 | Geauga County | 42 |
| 381 | Genesee County | 42 |
| 381 | Glenn County | 42 |
| 381 | Greenbrier County | 42 |
| 381 | Hampton city | 42 |
| 381 | Hancock County | 42 |
| 381 | Jefferson County | 42 |
| 381 | Jefferson Parish | 42 |
| 381 | Kane County | 42 |
| 381 | Kaufman County | 42 |
| 381 | Kent County | 42 |
| 381 | Lenoir County | 42 |
| 381 | Madison County | 42 |
| 381 | Murray County | 42 |
| 381 | Muscatine County | 42 |
| 381 | Natrona County | 42 |
| 381 | Navarro County | 42 |
| 381 | Ohio County | 42 |
| 381 | Okanogan County | 42 |
| 381 | Oldham County | 42 |
| 381 | Polk County | 42 |
| 381 | Polk County | 42 |
| 381 | Richland County | 42 |
| 381 | Roanoke County | 42 |
| 381 | Shasta County | 42 |
| 381 | Shelby County | 42 |
| 381 | Spokane County | 42 |
| 381 | St. Charles County | 42 |
| 381 | Swain County | 42 |
| 381 | Van Buren County | 42 |
| 381 | Washington County | 42 |
| 381 | Williamson County | 42 |
| 428 | Ada County | 41 |
| 428 | Adams County | 41 |
| 428 | Albany County | 41 |
| 428 | Albemarle County | 41 |
| 428 | Arkansas County | 41 |
| 428 | Berkshire County | 41 |
| 428 | Black Hawk County | 41 |
| 428 | Box Elder County | 41 |
| 428 | Bradford County | 41 |
| 428 | Bullitt County | 41 |
| 428 | Campbell County | 41 |
| 428 | Churchill County | 41 |
| 428 | Clay County | 41 |
| 428 | Colusa County | 41 |
| 428 | Converse County | 41 |
| 428 | Craighead County | 41 |
| 428 | Delaware County | 41 |
| 428 | Delta County | 41 |
| 428 | Elkhart County | 41 |
| 428 | Essex County | 41 |
| 428 | Florence County | 41 |
| 428 | Garfield County | 41 |
| 428 | Grant County | 41 |
| 428 | Greene County | 41 |
| 428 | Hampshire County | 41 |
| 428 | Hanover County | 41 |
| 428 | Harrison County | 41 |
| 428 | Jackson County | 41 |
| 428 | Kleberg County | 41 |
| 428 | Knox County | 41 |
| 428 | Licking County | 41 |
| 428 | Livingston County | 41 |
| 428 | Lorain County | 41 |
| 428 | Madison County | 41 |
| 428 | Marion County | 41 |
| 428 | Martin County | 41 |
| 428 | McMinn County | 41 |
| 428 | Middlesex County | 41 |
| 428 | Monongalia County | 41 |
| 428 | Montgomery County | 41 |
| 428 | Montgomery County | 41 |
| 428 | Nassau County | 41 |
| 428 | Outagamie County | 41 |
| 428 | Pike County | 41 |
| 428 | Pitt County | 41 |
| 428 | Pulaski County | 41 |
| 428 | Randall County | 41 |
| 428 | Richmond County | 41 |
| 428 | Sedgwick County | 41 |
| 428 | Sequoyah County | 41 |
| 428 | Spencer County | 41 |
| 428 | St. Clair County | 41 |
| 428 | St. Tammany Parish | 41 |
| 428 | Suffolk city | 41 |
| 428 | Sullivan County | 41 |
| 428 | Sumner County | 41 |
| 428 | Volusia County | 41 |
| 428 | Washington County | 41 |
| 428 | Westmoreland County | 41 |
| 428 | Wythe County | 41 |
| 488 | Adair County | 40 |
| 488 | Andrew County | 40 |
| 488 | Arlington County | 40 |
| 488 | Avery County | 40 |
| 488 | Baldwin County | 40 |
| 488 | Bell County | 40 |
| 488 | Berkeley County | 40 |
| 488 | Brown County | 40 |
| 488 | Butte County | 40 |
| 488 | Cabell County | 40 |
| 488 | Charles County | 40 |
| 488 | Chattooga County | 40 |
| 488 | Chesterfield County | 40 |
| 488 | Christian County | 40 |
| 488 | Citrus County | 40 |
| 488 | Collier County | 40 |
| 488 | Collin County | 40 |
| 488 | Coos County | 40 |
| 488 | Custer County | 40 |
| 488 | Douglas County | 40 |
| 488 | Edgecombe County | 40 |
| 488 | Effingham County | 40 |
| 488 | Franklin County | 40 |
| 488 | Giles County | 40 |
| 488 | Greene County | 40 |
| 488 | Hancock County | 40 |
| 488 | Ingham County | 40 |
| 488 | Johnson County | 40 |
| 488 | Johnston County | 40 |
| 488 | Kent County | 40 |
| 488 | Lake County | 40 |
| 488 | Lake County | 40 |
| 488 | Lee County | 40 |
| 488 | Lincoln County | 40 |
| 488 | Martin County | 40 |
| 488 | Miami County | 40 |
| 488 | Monroe County | 40 |
| 488 | Montgomery County | 40 |
| 488 | Ocean County | 40 |
| 488 | Olmsted County | 40 |
| 488 | Ozaukee County | 40 |
| 488 | Palm Beach County | 40 |
| 488 | Passaic County | 40 |
| 488 | Perry County | 40 |
| 488 | Plymouth County | 40 |
| 488 | Polk County | 40 |
| 488 | Rapides Parish | 40 |
| 488 | Rutland County | 40 |
| 488 | Simpson County | 40 |
| 488 | Snohomish County | 40 |
| 488 | Tangipahoa Parish | 40 |
| 488 | Umatilla County | 40 |
| 488 | Weston County | 40 |
| 488 | Wilson County | 40 |
| 488 | Wood County | 40 |
| 543 | Alachua County | 39 |
| 543 | Alexander County | 39 |
| 543 | Allegan County | 39 |
| 543 | Amador County | 39 |
| 543 | Anoka County | 39 |
| 543 | Ashtabula County | 39 |
| 543 | Benton County | 39 |
| 543 | Berrien County | 39 |
| 543 | Boone County | 39 |
| 543 | Brevard County | 39 |
| 543 | Caddo Parish | 39 |
| 543 | Callaway County | 39 |
| 543 | Calvert County | 39 |
| 543 | Caroline County | 39 |
| 543 | Cass County | 39 |
| 543 | Caswell County | 39 |
| 543 | Chittenden County | 39 |
| 543 | Columbia County | 39 |
| 543 | DeKalb County | 39 |
| 543 | Dukes County | 39 |
| 543 | Eau Claire County | 39 |
| 543 | Elmore County | 39 |
| 543 | Erie County | 39 |
| 543 | Flathead County | 39 |
| 543 | Garrett County | 39 |
| 543 | Grant County | 39 |
| 543 | Howard County | 39 |
| 543 | Klamath County | 39 |
| 543 | La Crosse County | 39 |
| 543 | Lackawanna County | 39 |
| 543 | Lee County | 39 |
| 543 | Lee County | 39 |
| 543 | Macomb County | 39 |
| 543 | McLennan County | 39 |
| 543 | Monterey County | 39 |
| 543 | Oakland County | 39 |
| 543 | Onondaga County | 39 |
| 543 | Orange County | 39 |
| 543 | Orange County | 39 |
| 543 | Racine County | 39 |
| 543 | Ramsey County | 39 |
| 543 | Rockingham County | 39 |
| 543 | Rockland County | 39 |
| 543 | San Benito County | 39 |
| 543 | San Francisco County | 39 |
| 543 | San Mateo County | 39 |
| 543 | Santa Cruz County | 39 |
| 543 | Santa Cruz County | 39 |
| 543 | Sarpy County | 39 |
| 543 | Sauk County | 39 |
| 543 | Seminole County | 39 |
| 543 | Sheridan County | 39 |
| 543 | Stafford County | 39 |
| 543 | Sumter County | 39 |
| 543 | Tuscaloosa County | 39 |
| 543 | Wakulla County | 39 |
| 543 | Warren County | 39 |
| 543 | Washington County | 39 |
| 543 | Washington County | 39 |
| 602 | Bonneville County | 38 |
| 602 | Boone County | 38 |
| 602 | Chautauqua County | 38 |
| 602 | Clallam County | 38 |
| 602 | Colbert County | 38 |
| 602 | Darlington County | 38 |
| 602 | Ector County | 38 |
| 602 | Fayette County | 38 |
| 602 | Fergus County | 38 |
| 602 | Greene County | 38 |
| 602 | Harrison County | 38 |
| 602 | Henrico County | 38 |
| 602 | Houston County | 38 |
| 602 | Iberville Parish | 38 |
| 602 | Indiana County | 38 |
| 602 | Jackson County | 38 |
| 602 | Johnson County | 38 |
| 602 | Johnson County | 38 |
| 602 | Loudoun County | 38 |
| 602 | Lyon County | 38 |
| 602 | Mercer County | 38 |
| 602 | Muskegon County | 38 |
| 602 | Noble County | 38 |
| 602 | Osage County | 38 |
| 602 | Park County | 38 |
| 602 | Portage County | 38 |
| 602 | Pottawattamie County | 38 |
| 602 | Powder River County | 38 |
| 602 | Rock County | 38 |
| 602 | Rockbridge County | 38 |
| 602 | Rockingham County | 38 |
| 602 | Scott County | 38 |
| 602 | Sheboygan County | 38 |
| 602 | Shoshone County | 38 |
| 602 | Siskiyou County | 38 |
| 602 | St. Louis County | 38 |
| 602 | Ste. Genevieve County | 38 |
| 602 | Sumter County | 38 |
| 602 | Taylor County | 38 |
| 602 | Washington County | 38 |
| 602 | Westchester County | 38 |
| 602 | Wood County | 38 |
| 602 | Woodbury County | 38 |
| 602 | Wyoming County | 38 |
| 602 | York County | 38 |
| 647 | Aiken County | 37 |
| 647 | Bennington County | 37 |
| 647 | Bossier Parish | 37 |
| 647 | Bremer County | 37 |
| 647 | Canadian County | 37 |
| 647 | Carter County | 37 |
| 647 | Carteret County | 37 |
| 647 | Choctaw County | 37 |
| 647 | Columbia County | 37 |
| 647 | Dawson County | 37 |
| 647 | DeKalb County | 37 |
| 647 | Fauquier County | 37 |
| 647 | Gloucester County | 37 |
| 647 | Glynn County | 37 |
| 647 | Goodhue County | 37 |
| 647 | Greenup County | 37 |
| 647 | Hancock County | 37 |
| 647 | Henry County | 37 |
| 647 | Hillsborough County | 37 |
| 647 | Jasper County | 37 |
| 647 | Jefferson County | 37 |
| 647 | LaPorte County | 37 |
| 647 | Linn County | 37 |
| 647 | Lycoming County | 37 |
| 647 | Marin County | 37 |
| 647 | Marion County | 37 |
| 647 | Minnehaha County | 37 |
| 647 | Monmouth County | 37 |
| 647 | Napa County | 37 |
| 647 | New Hanover County | 37 |
| 647 | Oconee County | 37 |
| 647 | Ottawa County | 37 |
| 647 | Parker County | 37 |
| 647 | Perry County | 37 |
| 647 | Pike County | 37 |
| 647 | Richland County | 37 |
| 647 | Roane County | 37 |
| 647 | Steuben County | 37 |
| 647 | Terrebonne Parish | 37 |
| 647 | Tioga County | 37 |
| 647 | Trego County | 37 |
| 647 | Trigg County | 37 |
| 647 | Union County | 37 |
| 647 | Wabash County | 37 |
| 647 | Walworth County | 37 |
| 647 | Washington County | 37 |
| 647 | Washington County | 37 |
| 694 | Aroostook County | 36 |
| 694 | Asotin County | 36 |
| 694 | Barnstable County | 36 |
| 694 | Benzie County | 36 |
| 694 | Big Horn County | 36 |
| 694 | Burleigh County | 36 |
| 694 | Cass County | 36 |
| 694 | Charles City County | 36 |
| 694 | Creek County | 36 |
| 694 | Culberson County | 36 |
| 694 | Dakota County | 36 |
| 694 | Delaware County | 36 |
| 694 | Denali Borough | 36 |
| 694 | Fond du Lac County | 36 |
| 694 | Forest County | 36 |
| 694 | Franklin County | 36 |
| 694 | Highlands County | 36 |
| 694 | Huron County | 36 |
| 694 | Indian River County | 36 |
| 694 | Kewaunee County | 36 |
| 694 | Kings County | 36 |
| 694 | Knox County | 36 |
| 694 | Knox County | 36 |
| 694 | Lancaster County | 36 |
| 694 | Lauderdale County | 36 |
| 694 | Lawrence County | 36 |
| 694 | Le Flore County | 36 |
| 694 | Madison County | 36 |
| 694 | Manatee County | 36 |
| 694 | Manistee County | 36 |
| 694 | Manitowoc County | 36 |
| 694 | Meade County | 36 |
| 694 | Mendocino County | 36 |
| 694 | Merrimack County | 36 |
| 694 | Missaukee County | 36 |
| 694 | Morgan County | 36 |
| 694 | Morris County | 36 |
| 694 | Multnomah County | 36 |
| 694 | Newton County | 36 |
| 694 | Okaloosa County | 36 |
| 694 | Oliver County | 36 |
| 694 | Orleans Parish | 36 |
| 694 | Ouachita Parish | 36 |
| 694 | Pasco County | 36 |
| 694 | Prince William County | 36 |
| 694 | Rosebud County | 36 |
| 694 | Shelby County | 36 |
| 694 | Smith County | 36 |
| 694 | Somerset County | 36 |
| 694 | Sonoma County | 36 |
| 694 | Stevens County | 36 |
| 694 | Warrick County | 36 |
| 694 | Wright County | 36 |
| 747 | Ashland County | 35 |
| 747 | Boone County | 35 |
| 747 | Brown County | 35 |
| 747 | Bucks County | 35 |
| 747 | Carroll County | 35 |
| 747 | Cheshire County | 35 |
| 747 | Claiborne County | 35 |
| 747 | Clinton County | 35 |
| 747 | Door County | 35 |
| 747 | Dunn County | 35 |
| 747 | Dyer County | 35 |
| 747 | Elk County | 35 |
| 747 | Floyd County | 35 |
| 747 | Grafton County | 35 |
| 747 | Gregg County | 35 |
| 747 | Hamilton County | 35 |
| 747 | Hood County | 35 |
| 747 | Horry County | 35 |
| 747 | Hunt County | 35 |
| 747 | Jackson County | 35 |
| 747 | Jefferson County | 35 |
| 747 | Knox County | 35 |
| 747 | Lake County | 35 |
| 747 | Mason County | 35 |
| 747 | Mayes County | 35 |
| 747 | McKenzie County | 35 |
| 747 | Monroe County | 35 |
| 747 | Montgomery County | 35 |
| 747 | Morgan County | 35 |
| 747 | Niagara County | 35 |
| 747 | Posey County | 35 |
| 747 | Prince Edward County | 35 |
| 747 | Putnam County | 35 |
| 747 | Tompkins County | 35 |
| 747 | Tucker County | 35 |
| 747 | Wayne County | 35 |
| 783 | Bay County | 34 |
| 783 | Billings County | 34 |
| 783 | Bristol city | 34 |
| 783 | Burke County | 34 |
| 783 | Chesterfield County | 34 |
| 783 | Clark County | 34 |
| 783 | Clark County | 34 |
| 783 | Coffee County | 34 |
| 783 | Dutchess County | 34 |
| 783 | Flagler County | 34 |
| 783 | Hendricks County | 34 |
| 783 | Jackson County | 34 |
| 783 | Jo Daviess County | 34 |
| 783 | Josephine County | 34 |
| 783 | Kent County | 34 |
| 783 | Lubbock County | 34 |
| 783 | Luzerne County | 34 |
| 783 | Lynchburg city | 34 |
| 783 | Lyon County | 34 |
| 783 | Marathon County | 34 |
| 783 | Maverick County | 34 |
| 783 | Mono County | 34 |
| 783 | Monroe County | 34 |
| 783 | Norfolk County | 34 |
| 783 | Osceola County | 34 |
| 783 | Oswego County | 34 |
| 783 | Phillips County | 34 |
| 783 | Plumas County | 34 |
| 783 | Rockwall County | 34 |
| 783 | Salem city | 34 |
| 783 | St. Lucie County | 34 |
| 783 | St. Martin Parish | 34 |
| 783 | Stearns County | 34 |
| 783 | Virginia Beach city | 34 |
| 783 | Washington County | 34 |
| 783 | Washington County | 34 |
| 783 | Wexford County | 34 |
| 783 | Williams County | 34 |
| 821 | Androscoggin County | 33 |
| 821 | Ascension Parish | 33 |
| 821 | Athens County | 33 |
| 821 | Baker County | 33 |
| 821 | Brazoria County | 33 |
| 821 | Clearfield County | 33 |
| 821 | Gallatin County | 33 |
| 821 | Leavenworth County | 33 |
| 821 | Liberty County | 33 |
| 821 | Macon County | 33 |
| 821 | Macoupin County | 33 |
| 821 | Oxford County | 33 |
| 821 | Pennington County | 33 |
| 821 | Penobscot County | 33 |
| 821 | Pointe Coupee Parish | 33 |
| 821 | Putnam County | 33 |
| 821 | Sanders County | 33 |
| 821 | Saratoga County | 33 |
| 821 | St. John the Baptist Parish | 33 |
| 821 | Thurston County | 33 |
| 821 | Tuscola County | 33 |
| 821 | Yalobusha County | 33 |
| 843 | Anchorage Municipality | 32 |
| 843 | Belknap County | 32 |
| 843 | Canyon County | 32 |
| 843 | Chelan County | 32 |
| 843 | Clark County | 32 |
| 843 | Codington County | 32 |
| 843 | Douglas County | 32 |
| 843 | Gilmer County | 32 |
| 843 | Lawrence County | 32 |
| 843 | Mille Lacs County | 32 |
| 843 | Nez Perce County | 32 |
| 843 | Susquehanna County | 32 |
| 855 | Archuleta County | 31 |
| 855 | Baker County | 31 |
| 855 | Becker County | 31 |
| 855 | Berkeley County | 31 |
| 855 | Clackamas County | 31 |
| 855 | Crow Wing County | 31 |
| 855 | Franklin County | 31 |
| 855 | Huntington County | 31 |
| 855 | Kittitas County | 31 |
| 855 | Kootenai County | 31 |
| 855 | Lake County | 31 |
| 855 | Lake County | 31 |
| 855 | Lawrence County | 31 |
| 855 | Lemhi County | 31 |
| 855 | Maury County | 31 |
| 855 | Polk County | 31 |
| 855 | Schoolcraft County | 31 |
| 855 | Stoddard County | 31 |
| 855 | Victoria County | 31 |
| 855 | Vilas County | 31 |
| 855 | Ward County | 31 |
| 855 | Wasco County | 31 |
| 855 | Yellowstone County | 31 |
| 878 | Crook County | 30 |
| 879 | Herkimer County | 29 |
| 879 | Jefferson County | 29 |
| 879 | Kennebec County | 29 |
| 879 | Mitchell County | 29 |
| 879 | Nassau County | 29 |
| 879 | Skagit County | 29 |
| 879 | St. James Parish | 29 |
| 879 | Valley County | 29 |
| 879 | Wallowa County | 29 |
| 879 | Whatcom County | 29 |
| 889 | Adams County | 28 |
| 889 | Carlton County | 28 |
| 889 | Cascade County | 28 |
| 889 | Honolulu County | 28 |
| 889 | Humboldt County | 28 |
| 889 | Mason County | 28 |
| 895 | Bonner County | 27 |
| 895 | Chase County | 27 |
| 895 | Columbia County | 27 |
| 895 | Grays Harbor County | 27 |
| 895 | Juneau City and Borough | 27 |
| 895 | Klickitat County | 27 |
| 895 | Lewis County | 27 |
| 902 | Beltrami County | 26 |
| 902 | Charlton County | 26 |
| 902 | Colleton County | 26 |
| 902 | Del Norte County | 26 |
| 902 | Deschutes County | 26 |
| 902 | Jefferson County | 26 |
| 902 | Pueblo County | 26 |
| 902 | Taney County | 26 |
| 902 | Twin Falls County | 26 |
| 902 | Union County | 26 |
| 912 | Brown County | 25 |
| 912 | Coos County | 25 |
| 912 | Hall County | 25 |
| 912 | Lake County | 25 |
| 912 | Matanuska-Susitna Borough | 25 |
| 912 | Potter County | 25 |
| 912 | Scotts Bluff County | 25 |
| 919 | Bannock County | 24 |
| 919 | Cowlitz County | 24 |
| 919 | Grant County | 24 |
| 919 | Hyde County | 24 |
| 919 | Kitsap County | 24 |
| 919 | Silver Bow County | 24 |
| 919 | Whitman County | 24 |
| 926 | Franklin County | 23 |
| 926 | Garfield County | 23 |
| 926 | Oneida County | 23 |
| 926 | Trinity County | 23 |
| 926 | Walla Walla County | 23 |
| 931 | Benton County | 22 |
| 931 | Columbia County | 22 |
| 931 | Cook County | 22 |
| 931 | Grant County | 22 |
| 935 | Chaves County | 21 |
| 935 | Franklin County | 21 |
| 935 | Hawaii County | 21 |
| 935 | San Juan County | 21 |
| 935 | Taos County | 21 |
| 935 | Winona County | 21 |
| 941 | Blaine County | 20 |
| 941 | Jerome County | 20 |
| 941 | Maui County | 20 |
| 941 | Norfolk city | 20 |
| 945 | Brooke County | 19 |
| 945 | Ravalli County | 19 |
| 947 | Cass County | 18 |
| 947 | Muskogee County | 18 |
| 949 | Adams County | 17 |
| 949 | Douglas County | 17 |
| 949 | Putnam County | 17 |
| 952 | Kauai County | 16 |
| 952 | Monroe County | 16 |
| 952 | Sheridan County | 16 |
| 952 | Thomas County | 16 |
| 956 | Belmont County | 15 |
| 956 | Cerro Gordo County | 15 |
| 956 | Ford County | 15 |
| 956 | Nye County | 15 |
| 960 | Aleutians East Borough | 14 |
| 960 | Custer County | 14 |
| 960 | Elko County | 14 |
| 960 | Georgetown County | 14 |
| 960 | Hughes County | 14 |
| 960 | Latah County | 14 |
| 960 | Mohave County | 14 |
| 960 | Platte County | 14 |
| 960 | Prowers County | 14 |
| 960 | Scioto County | 14 |
| 960 | Socorro County | 14 |
| 971 | Bethel Census Area | 13 |
| 971 | Cass County | 13 |
| 971 | Fremont County | 13 |
| 971 | Lincoln County | 13 |
| 971 | Roosevelt County | 13 |
| 971 | Routt County | 13 |
| 977 | Alamosa County | 12 |
| 977 | Catron County | 12 |
| 977 | Columbiana County | 12 |
| 977 | Keweenaw County | 12 |
| 977 | Lincoln County | 12 |
| 977 | Los Alamos County | 12 |
| 977 | Luna County | 12 |
| 977 | Powell County | 12 |
| 977 | Sherman County | 12 |
| 977 | Wayne County | 12 |
| 987 | Apache County | 11 |
| 987 | Kenai Peninsula Borough | 11 |
| 987 | Pitkin County | 11 |
| 987 | Windham County | 11 |
| 991 | Lake County | 10 |
| 992 | Carroll County | 9 |
| 992 | San Juan County | 9 |
| 994 | Custer County | 8 |
| 994 | Hopewell city | 8 |
| 994 | Jackson County | 8 |
| 994 | Winchester city | 8 |
| 998 | North Slope Borough | 6 |
| 999 | Alexandria city | 5 |
| 1000 | Harrison County | 2 |