Counties in Wyoming by share of days unhealthy for sensitive groups or worse (US EPA AQI)

Campbell County had the highest share of days unhealthy for sensitive groups or worse (US EPA AQI) of 18 counties in 2016, at 0.3%. Weston County had the lowest, at 0%. The median was 0%. Source: EPA.

Keep it in a collection in your library.
Highest0.3Campbell County
Median018 counties

Map of counties, 2016

Albany County: 0 %Big Horn County: 0 %Campbell County: 0.3 %Carbon County: 0 %Converse County: 0.3 %Fremont County: 0 %Goshen County: 0 %Laramie County: 0 %Lincoln County: 0 %Natrona County: 0 %Park County: 0 %Platte County: 0 %Sheridan County: 0.3 %Sublette County: 0.3 %Sweetwater County: 0 %Teton County: 0 %Uinta County: 0 %Weston County: 0 %
  • 0 and over
  • No data
%, 2016. Hatched areas have no value for this period. Source: Invokely calculation with data from EPA. Boundaries: U.S. Census Bureau cartographic boundary files.

All counties, 2016

Campbell County: 0.3 %Campbell County0.3Converse County: 0.3 %Converse County0.3Sheridan County: 0.3 %Sheridan County0.3Sublette County: 0.3 %Sublette County0.3Albany County: 0 %Albany County0Big Horn County: 0 %Big Horn County0Carbon County: 0 %Carbon County0Fremont County: 0 %Fremont County0Goshen County: 0 %Goshen County0Laramie County: 0 %Laramie County0Lincoln County: 0 %Lincoln County0Natrona County: 0 %Natrona County0Park County: 0 %Park County0Platte County: 0 %Platte County0Sweetwater County: 0 %Sweetwater County0Teton County: 0 %Teton County0Uinta County: 0 %Uinta County0Weston County: 0 %Weston County0Campbell County: 0.3 %Campbell County0.3Converse County: 0.3 %Converse County0.3Sheridan County: 0.3 %Sheridan County0.3Sublette County: 0.3 %Sublette County0.3Albany County: 0 %Albany County0Big Horn County: 0 %Big Horn County0Carbon County: 0 %Carbon County0Fremont County: 0 %Fremont County0Goshen County: 0 %Goshen County0Laramie County: 0 %Laramie County0Lincoln County: 0 %Lincoln County0Natrona County: 0 %Natrona County0Park County: 0 %Park County0Platte County: 0 %Platte County0Sweetwater County: 0 %Sweetwater County0Teton County: 0 %Teton County0Uinta County: 0 %Uinta County0Weston County: 0 %Weston County0
%. Source: Invokely calculation with data from EPA. Retrieved 2026-10-12.

Full ranking

RankCounties2016 (%)Change on 2015
1Campbell County0.3-0.5 pts
1Converse County0.3-1.1 pts
1Sheridan County0.3-0.2 pts
1Sublette County0.30 pts
5Albany County00 pts
5Big Horn County00 pts
5Carbon County0-0.3 pts
5Fremont County00 pts
5Goshen County0-1.2 pts
5Laramie County0-0.3 pts
5Lincoln County00 pts
5Natrona County00 pts
5Park County00 pts
5Platte County00 pts
5Sweetwater County0-1.1 pts
5Teton County0-0.3 pts
5Uinta County0-0.5 pts
5Weston County00 pts

Other periods

About this ranking

Days with a daily Air Quality Index above 100 (unhealthy for sensitive groups, unhealthy, very unhealthy or hazardous) as a percentage of the days of the year with an AQI in a US county. Calculated by Invokely from the day counts in the EPA AirData annual summaries; the counts are stored with each value.

Use the share rather than the number of days to compare counties, since the days with an AQI differ. United States counties with air quality monitors only, about 1,000 of some 3,100 in recent years; a county without monitors has no value. The number of days with an AQI differs between counties because some monitors run only in the ozone season.

Every value in the ranking comes from the same publisher and the same period, so the counties are compared on one definition. 3 counties with data in other periods have no value for 2016 and are left out rather than filled from another source. Equal values share a rank.

How to cite

U.S. Environmental Protection Agency, Air Quality System, AirData. EPA AirData annual AQI by county: days with an AQI above 100 as a share of days with an AQI, calculated with stored counts. https://aqs.epa.gov/aqsweb/airdata/download_files.html#Annual. Retrieved 2026-10-12.

Citation styles

The publisher is the author. Invokely is named only as the place the figures were read, where a style asks for it.

APA 7

U.S. Environmental Protection Agency. (2026). EPA AirData annual AQI by county: days with an AQI above 100 as a share of days with an AQI, calculated with stored counts (Counties in Wyoming by share of days unhealthy for sensitive groups or worse (US EPA AQI), 2016) [Data set]. Retrieved October 12, 2026, from https://aqs.epa.gov/aqsweb/airdata/download_files.html#Annual

MLA 9

EPA AirData annual AQI by county: days with an AQI above 100 as a share of days with an AQI, calculated with stored counts, Counties in Wyoming by share of days unhealthy for sensitive groups or worse (US EPA AQI), 2016. U.S. Environmental Protection Agency, 13 July 2026, https://aqs.epa.gov/aqsweb/airdata/download_files.html#Annual. Invokely, https://invokely.ai/rankings/unhealthy-air-quality-days-share/wyoming-counties?period=2016. Accessed 12 Oct. 2026.

Chicago (author-date)

U.S. Environmental Protection Agency. 2026. EPA AirData annual AQI by county: days with an AQI above 100 as a share of days with an AQI, calculated with stored counts. Counties in Wyoming by share of days unhealthy for sensitive groups or worse (US EPA AQI), 2016. Dataset. Accessed October 12, 2026. https://aqs.epa.gov/aqsweb/airdata/download_files.html#Annual. Also distributed by Invokely, https://invokely.ai/rankings/unhealthy-air-quality-days-share/wyoming-counties?period=2016.

Harvard

U.S. Environmental Protection Agency (2026) EPA AirData annual AQI by county: days with an AQI above 100 as a share of days with an AQI, calculated with stored counts, Counties in Wyoming by share of days unhealthy for sensitive groups or worse (US EPA AQI), 2016 [Dataset]. Available at: https://aqs.epa.gov/aqsweb/airdata/download_files.html#Annual, via Invokely: https://invokely.ai/rankings/unhealthy-air-quality-days-share/wyoming-counties?period=2016 (Accessed: 12 October 2026).

BibTeX
@misc{environmental_counties_in_wyoming_by_2016,
  author = {{U.S. Environmental Protection Agency}},
  title = {{EPA AirData annual AQI by county: days with an AQI above 100 as a share of days with an AQI, calculated with stored counts: Counties in Wyoming by share of days unhealthy for sensitive groups or worse (US EPA AQI), 2016}},
  year = {2026},
  howpublished = {Data set},
  url = {https://aqs.epa.gov/aqsweb/airdata/download_files.html#Annual},
  urldate = {2026-10-12},
  note = {Accessed via Invokely, https://invokely.ai/rankings/unhealthy-air-quality-days-share/wyoming-counties?period=2016. Publisher attribution: U.S. Environmental Protection Agency, Air Quality System, AirData. EPA AirData annual AQI by county: days with an AQI above 100 as a share of days with an AQI, calculated with stored counts. https://aqs.epa.gov/aqsweb/airdata/download\_files.html\#Annual. Retrieved 2026-10-12.},
}
RIS
TY  - DATA
AU  - U.S. Environmental Protection Agency
TI  - EPA AirData annual AQI by county: days with an AQI above 100 as a share of days with an AQI, calculated with stored counts: Counties in Wyoming by share of days unhealthy for sensitive groups or worse (US EPA AQI), 2016
PY  - 2026
DA  - 2026/07/13
PB  - U.S. Environmental Protection Agency
DB  - Invokely
UR  - https://aqs.epa.gov/aqsweb/airdata/download_files.html#Annual
L2  - https://invokely.ai/rankings/unhealthy-air-quality-days-share/wyoming-counties?period=2016
Y2  - 2026/10/12
N1  - Accessed via Invokely, https://invokely.ai/rankings/unhealthy-air-quality-days-share/wyoming-counties?period=2016.
N1  - Publisher attribution: U.S. Environmental Protection Agency, Air Quality System, AirData. EPA AirData annual AQI by county: days with an AQI above 100 as a share of days with an AQI, calculated with stored counts. https://aqs.epa.gov/aqsweb/airdata/download_files.html#Annual. Retrieved 2026-10-12.
ER  - 
Embed this chart

Paste this code into a web page or a blog post. The chart shows the latest figures as they are published, with the source and a link back to this page.

Sites that read oEmbed links, such as WordPress, can show the chart when you paste the link to this page.

Use this data in your AI agent

Invokely serves this figure to AI assistants through MCP and to code through a REST API, with the source and citation attached. Ask your assistant:

Rank Counties in Wyoming by share of days unhealthy for sensitive groups or worse (US EPA AQI) using official data, and cite the source.
rank_places {"indicator":"aqi_unhealthy_sensitive_or_worse_days_share","level":"province","within":"Wyoming","limit":10}
GET https://invokely.ai/api/v1/rank?indicator=aqi_unhealthy_sensitive_or_worse_days_share&level=province&within=Wyoming&limit=10

Connect Claude, ChatGPT or Cursor in one step. The trial answers 25 calls a day without an account.

Questions

Which county has the highest share of days unhealthy for sensitive groups or worse (US EPA AQI)?

Campbell County, with 0.3% in 2016, according to EPA.

Which county has the lowest share of days unhealthy for sensitive groups or worse (US EPA AQI)?

Weston County, with 0% in 2016.

Where does this ranking come from?

Every value comes from one source and one period, so the places are comparable: U.S. Environmental Protection Agency, EPA AirData annual AQI by county: days with an AQI above 100 as a share of days with an AQI, calculated with stored counts. Retrieved 2026-10-12. 3 counties have no value for 2016 and are not ranked.

Share of days unhealthy for sensitive groups or worse (US EPA AQI): other rankings

Counties in Wyoming: more rankings