Interpretation of Incidence Rates Data
Incidence Rate Report for Montana by County
Breast (All Stages^), 2018-2022
All Races (includes Hispanic), Female, All Ages
Sorted by Name
Explanation of Column HeadersIncidence Rate (95% Confidence Interval) - The incidence rate is based upon 100,000 people and is an annual rate (or average annual rate) based on the time period indicated. Rates are age-adjusted by 5-year age groups to the 2000 U.S. standard million population.
Recent Trends - This is an interpretation of the AAPC/APC:
- Rising when 95% confidence interval of AAPC/APC is above 0.
- Stable when 95% confidence interval of AAPC/APC includes 0.
- Falling when 95% confidence interval of AAPC/APC is below 0.
AAPC/APC (95% Confidence Interval) - the change in rate over time
- Average Annual Percent Change - AAPCs are based upon APCs that were calculated by Joinpoint Regression Program
- Annual Percent Change - APCs calculated in SEER*Stat.
Other Notes
- Larger confidence intervals indicate less stability of the data. This is often due to low counts that are not quite low enough to be suppressed.
- Data is currently being suppressed if there are fewer than 16 counts for the time period.
Line by Line Interpretation of the Report
Montana2
- 2023 Rural-Urban Continuum Codes Φ : N/A
- Rate : The incidence rate is 137.5 with a 95% confidence interval from 133.4 to 141.7 and 955 average annual cases over 2018-2022.
- CI*Rank ⋔ : N/A
- Recent Trend : The trend is because the trend is 0.7 with a 95% confidence interval from 0.3 to 1.1.
US (SEER+NPCR)1
- 2023 Rural-Urban Continuum Codes Φ : N/A
- Rate : The incidence rate is 131.3 with a 95% confidence interval from 131.1 to 131.6 and 270,245 average annual cases over 2018-2022.
- CI*Rank ⋔ : N/A
- Recent Trend : The trend is because the trend is 0.6 with a 95% confidence interval from 0.5 to 0.8.
Beaverhead County2
- 2023 Rural-Urban Continuum Codes Φ : Rural
- Rate : The incidence rate is 113.1 with a 95% confidence interval from 76.2 to 163.0 and 7 average annual cases over 2018-2022.
- CI*Rank ⋔ : 30 (2, 37)
- Recent Trend : The trend is because the trend is -0.5 with a 95% confidence interval from -3.1 to 2.2.
Big Horn County2
- 2023 Rural-Urban Continuum Codes Φ : Rural
- Rate : The incidence rate is 138.3 with a 95% confidence interval from 100.5 to 185.6 and 10 average annual cases over 2018-2022.
- CI*Rank ⋔ : 10 (1, 36)
- Recent Trend : The trend is because the trend is 1.8 with a 95% confidence interval from -2.7 to 7.1.
Blaine County2
- 2023 Rural-Urban Continuum Codes Φ : Rural
- Rate : The incidence rate is 94.8 with a 95% confidence interval from 53.1 to 155.6 and 3 average annual cases over 2018-2022.
- CI*Rank ⋔ : 35 (3, 37)
- Recent Trend : The trend is because the trend is -5.0 with a 95% confidence interval from -23.4 to -0.7.
Broadwater County2
- 2023 Rural-Urban Continuum Codes Φ : Urban
- Rate : The incidence rate is 84.1 with a 95% confidence interval from 50.8 to 134.2 and 4 average annual cases over 2018-2022.
- CI*Rank ⋔ : 37 (9, 37)
- Recent Trend : The trend is because the trend is -0.6 with a 95% confidence interval from -4.7 to 4.2.
Carbon County2
- 2023 Rural-Urban Continuum Codes Φ : Urban
- Rate : The incidence rate is 132.8 with a 95% confidence interval from 94.8 to 182.7 and 10 average annual cases over 2018-2022.
- CI*Rank ⋔ : 16 (1, 36)
- Recent Trend : The trend is because the trend is 0.9 with a 95% confidence interval from -2.5 to 4.8.
Cascade County2
- 2023 Rural-Urban Continuum Codes Φ : Urban
- Rate : The incidence rate is 123.2 with a 95% confidence interval from 109.4 to 138.2 and 67 average annual cases over 2018-2022.
- CI*Rank ⋔ : 26 (10, 32)
- Recent Trend : The trend is because the trend is -1.6 with a 95% confidence interval from -11.9 to 0.9.
Chouteau County2
- 2023 Rural-Urban Continuum Codes Φ : Rural
- Rate : The incidence rate is 90.3 with a 95% confidence interval from 50.5 to 151.1 and 4 average annual cases over 2018-2022.
- CI*Rank ⋔ : 36 (4, 37)
- Recent Trend : The trend is because the trend is -2.1 with a 95% confidence interval from -7.5 to 2.7.
Custer County2
- 2023 Rural-Urban Continuum Codes Φ : Rural
- Rate : The incidence rate is 150.3 with a 95% confidence interval from 113.5 to 196.3 and 13 average annual cases over 2018-2022.
- CI*Rank ⋔ : 7 (1, 33)
- Recent Trend : The trend is because the trend is 3.9 with a 95% confidence interval from 0.1 to 17.3.
Dawson County2
- 2023 Rural-Urban Continuum Codes Φ : Rural
- Rate : The incidence rate is 151.2 with a 95% confidence interval from 105.6 to 210.7 and 8 average annual cases over 2018-2022.
- CI*Rank ⋔ : 6 (1, 36)
- Recent Trend : The trend is because the trend is -2.0 with a 95% confidence interval from -5.9 to 1.5.
Deer Lodge County2
- 2023 Rural-Urban Continuum Codes Φ : Rural
- Rate : The incidence rate is 96.7 with a 95% confidence interval from 65.9 to 140.6 and 8 average annual cases over 2018-2022.
- CI*Rank ⋔ : 34 (9, 37)
- Recent Trend : The trend is because the trend is 0.9 with a 95% confidence interval from -3.4 to 5.5.
Fergus County2
- 2023 Rural-Urban Continuum Codes Φ : Rural
- Rate : The incidence rate is 104.1 with a 95% confidence interval from 73.6 to 144.3 and 9 average annual cases over 2018-2022.
- CI*Rank ⋔ : 33 (7, 37)
- Recent Trend : The trend is because the trend is -0.8 with a 95% confidence interval from -4.6 to 2.9.
Flathead County2
- 2023 Rural-Urban Continuum Codes Φ : Rural
- Rate : The incidence rate is 140.1 with a 95% confidence interval from 127.4 to 153.8 and 101 average annual cases over 2018-2022.
- CI*Rank ⋔ : 9 (5, 25)
- Recent Trend : The trend is because the trend is 0.2 with a 95% confidence interval from -0.7 to 1.3.
Gallatin County2
- 2023 Rural-Urban Continuum Codes Φ : Urban
- Rate : The incidence rate is 134.1 with a 95% confidence interval from 120.5 to 148.9 and 75 average annual cases over 2018-2022.
- CI*Rank ⋔ : 15 (6, 28)
- Recent Trend : The trend is because the trend is -0.6 with a 95% confidence interval from -1.6 to 0.6.
Glacier County2
- 2023 Rural-Urban Continuum Codes Φ : Rural
- Rate : The incidence rate is 120.2 with a 95% confidence interval from 83.7 to 166.6 and 8 average annual cases over 2018-2022.
- CI*Rank ⋔ : 28 (2, 37)
- Recent Trend : The trend is because the trend is -1.6 with a 95% confidence interval from -6.1 to 2.4.
Hill County2
- 2023 Rural-Urban Continuum Codes Φ : Rural
- Rate : The incidence rate is 127.8 with a 95% confidence interval from 94.7 to 168.7 and 11 average annual cases over 2018-2022.
- CI*Rank ⋔ : 21 (2, 36)
- Recent Trend : The trend is because the trend is -0.7 with a 95% confidence interval from -3.2 to 1.8.
Jefferson County2
- 2023 Rural-Urban Continuum Codes Φ : Urban
- Rate : The incidence rate is 130.9 with a 95% confidence interval from 96.3 to 175.3 and 12 average annual cases over 2018-2022.
- CI*Rank ⋔ : 17 (1, 36)
- Recent Trend : The trend is because the trend is 1.4 with a 95% confidence interval from -0.9 to 4.0.
Lake County2
- 2023 Rural-Urban Continuum Codes Φ : Rural
- Rate : The incidence rate is 168.2 with a 95% confidence interval from 143.3 to 196.5 and 39 average annual cases over 2018-2022.
- CI*Rank ⋔ : 2 (1, 19)
- Recent Trend : The trend is because the trend is 1.3 with a 95% confidence interval from -1.3 to 4.2.
Lewis and Clark County2
- 2023 Rural-Urban Continuum Codes Φ : Urban
- Rate : The incidence rate is 123.7 with a 95% confidence interval from 108.9 to 140.0 and 58 average annual cases over 2018-2022.
- CI*Rank ⋔ : 24 (9, 33)
- Recent Trend : The trend is because the trend is -0.3 with a 95% confidence interval from -1.6 to 1.0.
Lincoln County2
- 2023 Rural-Urban Continuum Codes Φ : Rural
- Rate : The incidence rate is 122.3 with a 95% confidence interval from 96.2 to 154.2 and 20 average annual cases over 2018-2022.
- CI*Rank ⋔ : 27 (4, 36)
- Recent Trend : The trend is because the trend is -0.1 with a 95% confidence interval from -2.5 to 2.4.
Madison County2
- 2023 Rural-Urban Continuum Codes Φ : Rural
- Rate : The incidence rate is 117.9 with a 95% confidence interval from 81.6 to 168.2 and 9 average annual cases over 2018-2022.
- CI*Rank ⋔ : 29 (2, 37)
- Recent Trend : The trend is because the trend is 1.7 with a 95% confidence interval from -2.8 to 7.3.
Missoula County2
- 2023 Rural-Urban Continuum Codes Φ : Urban
- Rate : The incidence rate is 155.7 with a 95% confidence interval from 142.1 to 170.4 and 104 average annual cases over 2018-2022.
- CI*Rank ⋔ : 5 (2, 17)
- Recent Trend : The trend is because the trend is 1.4 with a 95% confidence interval from 0.3 to 2.7.
Musselshell County2
- 2023 Rural-Urban Continuum Codes Φ : Rural
- Rate : The incidence rate is 128.7 with a 95% confidence interval from 81.0 to 200.8 and 6 average annual cases over 2018-2022.
- CI*Rank ⋔ : 19 (1, 37)
- Recent Trend : The trend is because the trend is 4.0 with a 95% confidence interval from -0.1 to 9.1.
Park County2
- 2023 Rural-Urban Continuum Codes Φ : Rural
- Rate : The incidence rate is 123.4 with a 95% confidence interval from 95.8 to 157.5 and 16 average annual cases over 2018-2022.
- CI*Rank ⋔ : 25 (3, 36)
- Recent Trend : The trend is because the trend is -0.6 with a 95% confidence interval from -3.3 to 2.2.
Phillips County2
- 2023 Rural-Urban Continuum Codes Φ : Rural
- Rate : The incidence rate is 137.8 with a 95% confidence interval from 77.9 to 228.2 and 4 average annual cases over 2018-2022.
- CI*Rank ⋔ : 12 (1, 37)
- Recent Trend : The trend is because the trend is 0.9 with a 95% confidence interval from -4.0 to 6.3.
Pondera County2
- 2023 Rural-Urban Continuum Codes Φ : Rural
- Rate : The incidence rate is 138.2 with a 95% confidence interval from 85.2 to 212.3 and 5 average annual cases over 2018-2022.
- CI*Rank ⋔ : 11 (1, 37)
- Recent Trend : The trend is because the trend is -0.6 with a 95% confidence interval from -3.8 to 2.3.
Powell County2
- 2023 Rural-Urban Continuum Codes Φ : Rural
- Rate : The incidence rate is 148.1 with a 95% confidence interval from 96.2 to 222.1 and 6 average annual cases over 2018-2022.
- CI*Rank ⋔ : 8 (1, 36)
- Recent Trend : The trend is because the trend is -0.1 with a 95% confidence interval from -4.4 to 4.2.
Ravalli County2
- 2023 Rural-Urban Continuum Codes Φ : Rural
- Rate : The incidence rate is 136.9 with a 95% confidence interval from 117.8 to 158.6 and 47 average annual cases over 2018-2022.
- CI*Rank ⋔ : 13 (4, 30)
- Recent Trend : The trend is because the trend is 1.3 with a 95% confidence interval from -0.6 to 3.3.
Richland County2
- 2023 Rural-Urban Continuum Codes Φ : Rural
- Rate : The incidence rate is 107.7 with a 95% confidence interval from 72.6 to 154.1 and 6 average annual cases over 2018-2022.
- CI*Rank ⋔ : 32 (4, 37)
- Recent Trend : The trend is because the trend is 0.2 with a 95% confidence interval from -4.3 to 4.9.
Roosevelt County2
- 2023 Rural-Urban Continuum Codes Φ : Rural
- Rate : The incidence rate is 108.7 with a 95% confidence interval from 71.0 to 159.0 and 6 average annual cases over 2018-2022.
- CI*Rank ⋔ : 31 (3, 37)
- Recent Trend : The trend is because the trend is -3.1 with a 95% confidence interval from -6.6 to -0.2.
Rosebud County2
- 2023 Rural-Urban Continuum Codes Φ : Rural
- Rate : The incidence rate is 159.0 with a 95% confidence interval from 107.0 to 227.1 and 7 average annual cases over 2018-2022.
- CI*Rank ⋔ : 4 (1, 35)
- Recent Trend : The trend is because the trend is 3.2 with a 95% confidence interval from -0.3 to 7.4.
Sanders County2
- 2023 Rural-Urban Continuum Codes Φ : Rural
- Rate : The incidence rate is 124.5 with a 95% confidence interval from 89.5 to 170.1 and 12 average annual cases over 2018-2022.
- CI*Rank ⋔ : 22 (1, 37)
- Recent Trend : The trend is because the trend is 1.2 with a 95% confidence interval from -1.4 to 4.1.
Silver Bow County2
- 2023 Rural-Urban Continuum Codes Φ : Rural
- Rate : The incidence rate is 134.2 with a 95% confidence interval from 111.9 to 159.8 and 30 average annual cases over 2018-2022.
- CI*Rank ⋔ : 14 (3, 32)
- Recent Trend : The trend is because the trend is 0.6 with a 95% confidence interval from -1.9 to 3.1.
Stillwater County2
- 2023 Rural-Urban Continuum Codes Φ : Urban
- Rate : The incidence rate is 186.9 with a 95% confidence interval from 138.0 to 249.0 and 12 average annual cases over 2018-2022.
- CI*Rank ⋔ : 1 (1, 24)
- Recent Trend : The trend is because the trend is 1.5 with a 95% confidence interval from -1.5 to 4.9.
Sweet Grass County2
- 2023 Rural-Urban Continuum Codes Φ : Rural
- Rate : The incidence rate is 130.5 with a 95% confidence interval from 76.5 to 217.2 and 4 average annual cases over 2018-2022.
- CI*Rank ⋔ : 18 (1, 37)
- Recent Trend :
Teton County2
- 2023 Rural-Urban Continuum Codes Φ : Rural
- Rate : The incidence rate is 123.7 with a 95% confidence interval from 77.7 to 188.6 and 5 average annual cases over 2018-2022.
- CI*Rank ⋔ : 23 (1, 37)
- Recent Trend : The trend is because the trend is -1.8 with a 95% confidence interval from -7.1 to 3.4.
Valley County2
- 2023 Rural-Urban Continuum Codes Φ : Rural
- Rate : The incidence rate is 128.4 with a 95% confidence interval from 82.2 to 191.6 and 6 average annual cases over 2018-2022.
- CI*Rank ⋔ : 20 (1, 37)
- Recent Trend : The trend is because the trend is 2.4 with a 95% confidence interval from -0.3 to 5.3.
Yellowstone County2
- 2023 Rural-Urban Continuum Codes Φ : Urban
- Rate : The incidence rate is 164.2 with a 95% confidence interval from 153.0 to 176.2 and 172 average annual cases over 2018-2022.
- CI*Rank ⋔ : 3 (1, 12)
- Recent Trend : The trend is because the trend is 2.0 with a 95% confidence interval from 0.5 to 3.7.
Notes:
Created by statecancerprofiles.cancer.gov on 03/14/2026 7:20 pm.
State Cancer Registries may provide more current or more local data.
Trend
Rising when 95% confidence interval of average annual percent change is above 0.
Stable when 95% confidence interval of average annual percent change includes 0.
Falling when 95% confidence interval of average annual percent change is below 0.
Rising when 95% confidence interval of average annual percent change is above 0.
Stable when 95% confidence interval of average annual percent change includes 0.
Falling when 95% confidence interval of average annual percent change is below 0.
† Incidence rates (cases per 100,000 population per year) are age-adjusted to the 2000 US standard population (SEER areas use 20 age groups and NPCR areas use 19 age groups). Rates are for invasive cancer only (except for bladder cancer which is invasive and in situ) or unless otherwise specified. Rates calculated using SEER*Stat. Population counts for denominators are based on Census populations as modified by NCI. The US Population Data File is used for SEER and NPCR incidence rates.
‡ Incidence data come from different sources. The Average Annual Percent Change (AAPC) is based on the APCs calculated by Joinpoint. Due to data availability issues, the time period used in the calculation of the joinpoint regression model may differ for selected counties.
Rates and trends are computed using different standards for malignancy. For more information see malignant.html.
^ All Stages refers to any stage. Due to changes in stage coding, Combined Summary Stage with Expanded Regional Codes (2004+) is used for data from Surveillance, Epidemiology, and End Results (SEER) databases and Merged Summary Stage is used for data from National Program of Cancer Registries databases. Due to the increased complexity with staging, other staging variables maybe used if necessary.
⋔ Results presented with the CI*Rank statistics help show the usefulness of ranks. For example, ranks for relatively rare diseases or less populated areas may be essentially meaningless because of their large variability, but ranks for more common diseases in densely populated regions can be very useful. The rates used in CI*Rank are all age-adjusted to the 2000 US standard population using 19 age groups for SEER and NPCR areas. More information about methodology can be found on the CI*Rank website.
Φ Rural–urban county classifications are based on the 2023 USDA Rural–Urban Continuum Codes (except for Connecticut Counties which use 2013 codes). State-level cancer rates for rural areas are calculated using cancer cases registered exclusively in rural counties, while state-level cancer rates for urban areas are calculated using cases registered exclusively in urban counties.
1 Source: National Program of Cancer Registries and Surveillance, Epidemiology, and End Results SEER*Stat Database - United States Department of Health and Human Services, Centers for Disease Control and Prevention and National Cancer Institute. Based on the 2024 submission.
2 Source: National Program of Cancer Registries SEER*Stat Database - United States Department of Health and Human Services, Centers for Disease Control and Prevention (based on the 2024 submission).
* Data has been suppressed to ensure confidentiality and stability of rate estimates. Counts are suppressed if fewer than 16 records were reported in a specific area-sex-race category.
Data for United States does not include Puerto Rico.


