Median Air Quality Index (US EPA) in Dane County

Median Air Quality Index (US EPA) in Dane County was 41 in 2025, according to the U.S. Environmental Protection Agency. That is down 1 from 2024.

2025, index41
Change on 2024-1
Series high552010
Series low271991

Next release: Tuesday, 13 July 2027, estimated by Invokely from past publication dates (low confidence), not announced by the publisher. Release calendar

Get an email when a new figure is out or this one is revised.
Keep it in a collection in your library.

Median Air Quality Index (US EPA) in Dane County, 1980 to 2025

203040506019801987199420012008201520251980: 37 index1981: 30 index1982: 34 index1983: 31 index1984: 34 index1985: 35 index1986: 31 index1987: 29 index1988: 32 index1989: 31 index1990: 28 index1991: 27 index1992: 27 index1993: 30 index1994: 32 index1995: 31 index1996: 28 index1997: 29 index1998: 37 index1999: 44 index2000: 35 index2001: 43 index2002: 48 index2003: 49 index2004: 42 index2005: 49 index2006: 43 index2007: 54 index2008: 54 index2009: 49 index2010: 55 index2011: 50 index2012: 52 index2013: 51 index2014: 47 index2015: 44 index2016: 41 index2017: 42 index2018: 46 index2019: 43 index2020: 44 index2021: 48 index2022: 45 index2023: 50 index2024: 42 index2025: 41 index203040506019801996201220251980: 37 index1981: 30 index1982: 34 index1983: 31 index1984: 34 index1985: 35 index1986: 31 index1987: 29 index1988: 32 index1989: 31 index1990: 28 index1991: 27 index1992: 27 index1993: 30 index1994: 32 index1995: 31 index1996: 28 index1997: 29 index1998: 37 index1999: 44 index2000: 35 index2001: 43 index2002: 48 index2003: 49 index2004: 42 index2005: 49 index2006: 43 index2007: 54 index2008: 54 index2009: 49 index2010: 55 index2011: 50 index2012: 52 index2013: 51 index2014: 47 index2015: 44 index2016: 41 index2017: 42 index2018: 46 index2019: 43 index2020: 44 index2021: 48 index2022: 45 index2023: 50 index2024: 42 index2025: 41 index
index. Source: EPA, EPA AirData annual AQI by county: median daily AQI. Retrieved 2026-10-12, published 2026-07-13.
All 46 values
Periodindex
202541
202442
202350
202245
202148
202044
201943
201846
201742
201641
201544
201447
201351
201252
201150
201055
200949
200854
200754
200643
200549
200442
200349
200248
200143
200035
199944
199837
199729
199628
199531
199432
199330
199227
199127
199028
198931
198832
198729
198631
198535
198434
198331
198234
198130
198037

Dane County compared with nearby places

Ashland County: 36 indexBrown County: 37 indexColumbia County: 40 indexDane County: 41 indexDodge County: 40 indexDoor County: 38 indexEau Claire County: 38 indexFond du Lac County: 37 indexForest County: 39 indexGrant County: 37 indexJackson County: 36 indexJefferson County: 40 indexKenosha County: 42 indexKewaunee County: 39 indexLa Crosse County: 37 indexManitowoc County: 36 indexMarathon County: 36 indexMilwaukee County: 43 indexMonroe County: 36 indexOutagamie County: 38 indexOzaukee County: 36 indexRacine County: 41 indexRock County: 42 indexSauk County: 35 indexSheboygan County: 41 indexTaylor County: 34 indexVilas County: 36 indexWalworth County: 42 indexWaukesha County: 41 index
  • Under 36
  • 36 to 37
  • 37 to 39
  • 39 to 41
  • 41 and over
  • No data
Median Air Quality Index (US EPA), 2025, index. Dane County is outlined. Same source and period for every area shown. Source: U.S. Environmental Protection Agency. Boundaries: U.S. Census Bureau cartographic boundary files.

Rankings

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.

More on how it is measured
  • 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.

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.

Report a problem with this figure

How to cite

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.

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: median daily AQI (Median Air Quality Index (US EPA), Dane County, 1980 to 2025) [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: median daily AQI, Median Air Quality Index (US EPA), Dane County, 1980 to 2025. U.S. Environmental Protection Agency, 13 July 2026, https://aqs.epa.gov/aqsweb/airdata/download_files.html#Annual. Invokely, https://invokely.ai/en/median-air-quality-index/dane-county-wisconsin. Accessed 12 Oct. 2026.

Chicago (author-date)

U.S. Environmental Protection Agency. 2026. EPA AirData annual AQI by county: median daily AQI. Median Air Quality Index (US EPA), Dane County, 1980 to 2025. Dataset. Accessed October 12, 2026. https://aqs.epa.gov/aqsweb/airdata/download_files.html#Annual. Also distributed by Invokely, https://invokely.ai/en/median-air-quality-index/dane-county-wisconsin.

Harvard

U.S. Environmental Protection Agency (2026) EPA AirData annual AQI by county: median daily AQI, Median Air Quality Index (US EPA), Dane County, 1980 to 2025 [Dataset]. Available at: https://aqs.epa.gov/aqsweb/airdata/download_files.html#Annual, via Invokely: https://invokely.ai/en/median-air-quality-index/dane-county-wisconsin (Accessed: 12 October 2026).

BibTeX
@misc{environmental_median_air_quality_index_2025,
  author = {{U.S. Environmental Protection Agency}},
  title = {{EPA AirData annual AQI by county: median daily AQI: Median Air Quality Index (US EPA), Dane County, 1980 to 2025}},
  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/en/median-air-quality-index/dane-county-wisconsin. Publisher attribution: 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.},
}
RIS
TY  - DATA
AU  - U.S. Environmental Protection Agency
TI  - EPA AirData annual AQI by county: median daily AQI: Median Air Quality Index (US EPA), Dane County, 1980 to 2025
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/en/median-air-quality-index/dane-county-wisconsin
Y2  - 2026/10/12
N1  - Accessed via Invokely, https://invokely.ai/en/median-air-quality-index/dane-county-wisconsin.
N1  - Publisher attribution: 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.
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:

What is the latest median Air Quality Index (US EPA) in Dane County? Cite the source.
get_value {"indicator":"aqi_median","place":"us-county-55025"}
GET https://invokely.ai/api/v1/value?indicator=aqi_median&place=us-county-55025

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

Questions

What is the median Air Quality Index (US EPA) in Dane County?

Median Air Quality Index (US EPA) in Dane County was 41 in 2025, according to the U.S. Environmental Protection Agency. That is down 1 from 2024.

Where does this figure come from?

U.S. Environmental Protection Agency. EPA AirData annual AQI by county: median daily AQI. Retrieved by Invokely on 2026-10-12.

What was the highest median Air Quality Index (US EPA) in Dane County?

55 in 2010, the highest value since 1980 in this series.

Related statistics for Dane County

All statistics for Dane County | Dane County in figures