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Interpretation of Incidence Rates Data

Incidence Rate Report for Illinois by County

All Races (includes Hispanic), Female, Ovary, All Ages
Sorted by Rate

Explanation of Column Headers

Incidence 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.

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


    Illinois6,10
    • Rate : The incidence rate is 12.4 with a 95% confidence interval from 12.0 to 12.7.
    • Average Annual Count : The count is 899.
    • Rate Period : The period for the rate is 2007-2011.
    • Recent Trend : falling falling trend
    • Recent AAPC : -2.4
    US (SEER+NPCR)1,10
    • Rate : The incidence rate is 12.0 with a 95% confidence interval from 12.0 to 12.1.
    • Average Annual Count : The count is 21,341 §.
    • Rate Period : The period for the rate is 2007-2011.
    • Recent Trend : falling falling trend
    • Recent AAPC : -2.9
    Kankakee County6,10
    • Rate : The incidence rate is 8.8 with a 95% confidence interval from 5.8 to 12.8.
    • Average Annual Count : The count is 6.
    • Rate Period : The period for the rate is 2007-2011.
    • Recent Trend : stable stable trend
    • Recent AAPC : -12.3
    Kendall County6,10
    • Rate : The incidence rate is 8.8 with a 95% confidence interval from 5.2 to 13.8.
    • Average Annual Count : The count is 4.
    • Rate Period : The period for the rate is 2007-2011.
    • Recent Trend : stable stable trend
    • Recent AAPC : -20.1
    Knox County6,10
    • Rate : The incidence rate is 9.2 with a 95% confidence interval from 5.3 to 15.3.
    • Average Annual Count : The count is 4.
    • Rate Period : The period for the rate is 2007-2011.
    • Recent Trend : stable stable trend
    • Recent AAPC : 0
    Champaign County6,10
    • Rate : The incidence rate is 9.8 with a 95% confidence interval from 7.2 to 13.2.
    • Average Annual Count : The count is 9.
    • Rate Period : The period for the rate is 2007-2011.
    • Recent Trend : stable stable trend
    • Recent AAPC : -4.1
    Henry County6,10
    • Rate : The incidence rate is 9.9 with a 95% confidence interval from 5.8 to 16.2.
    • Average Annual Count : The count is 4.
    • Rate Period : The period for the rate is 2007-2011.
    • Recent Trend : stable stable trend
    • Recent AAPC : -0.7
    Macoupin County6,10
    • Rate : The incidence rate is 10.1 with a 95% confidence interval from 5.7 to 16.9.
    • Average Annual Count : The count is 3.
    • Rate Period : The period for the rate is 2007-2011.
    • Recent Trend : stable stable trend
    • Recent AAPC : -4.4
    St. Clair County6,10
    • Rate : The incidence rate is 10.7 with a 95% confidence interval from 8.5 to 13.2.
    • Average Annual Count : The count is 17.
    • Rate Period : The period for the rate is 2007-2011.
    • Recent Trend : stable stable trend
    • Recent AAPC : 10.1
    McLean County6,10
    • Rate : The incidence rate is 11.0 with a 95% confidence interval from 8.0 to 14.7.
    • Average Annual Count : The count is 9.
    • Rate Period : The period for the rate is 2007-2011.
    • Recent Trend : stable stable trend
    • Recent AAPC : -9.8
    Ogle County6,10
    • Rate : The incidence rate is 11.1 with a 95% confidence interval from 6.6 to 17.7.
    • Average Annual Count : The count is 4.
    • Rate Period : The period for the rate is 2007-2011.
    • Recent Trend : stable stable trend
    • Recent AAPC : -11.1
    Macon County6,10
    • Rate : The incidence rate is 11.3 with a 95% confidence interval from 8.1 to 15.4.
    • Average Annual Count : The count is 9.
    • Rate Period : The period for the rate is 2007-2011.
    • Recent Trend : stable stable trend
    • Recent AAPC : -3.3
    Kane County6,10
    • Rate : The incidence rate is 11.5 with a 95% confidence interval from 9.7 to 13.7.
    • Average Annual Count : The count is 28.
    • Rate Period : The period for the rate is 2007-2011.
    • Recent Trend : falling falling trend
    • Recent AAPC : -17.3
    Lake County6,10
    • Rate : The incidence rate is 11.6 with a 95% confidence interval from 10.0 to 13.3.
    • Average Annual Count : The count is 42.
    • Rate Period : The period for the rate is 2007-2011.
    • Recent Trend : stable stable trend
    • Recent AAPC : -2.6
    Will County6,10
    • Rate : The incidence rate is 11.6 with a 95% confidence interval from 9.9 to 13.4.
    • Average Annual Count : The count is 37.
    • Rate Period : The period for the rate is 2007-2011.
    • Recent Trend : stable stable trend
    • Recent AAPC : -4
    Madison County6,10
    • Rate : The incidence rate is 11.6 with a 95% confidence interval from 9.3 to 14.3.
    • Average Annual Count : The count is 18.
    • Rate Period : The period for the rate is 2007-2011.
    • Recent Trend : stable stable trend
    • Recent AAPC : -4.6
    Sangamon County6,10
    • Rate : The incidence rate is 11.9 with a 95% confidence interval from 9.2 to 15.0.
    • Average Annual Count : The count is 15.
    • Rate Period : The period for the rate is 2007-2011.
    • Recent Trend : rising rising trend
    • Recent AAPC : 16.4
    Rock Island County6,10
    • Rate : The incidence rate is 11.9 with a 95% confidence interval from 9.0 to 15.6.
    • Average Annual Count : The count is 12.
    • Rate Period : The period for the rate is 2007-2011.
    • Recent Trend : stable stable trend
    • Recent AAPC : -9.5
    Tazewell County6,10
    • Rate : The incidence rate is 12.0 with a 95% confidence interval from 8.9 to 15.9.
    • Average Annual Count : The count is 11.
    • Rate Period : The period for the rate is 2007-2011.
    • Recent Trend : stable stable trend
    • Recent AAPC : -3.1
    DuPage County6,10
    • Rate : The incidence rate is 12.1 with a 95% confidence interval from 10.8 to 13.6.
    • Average Annual Count : The count is 62.
    • Rate Period : The period for the rate is 2007-2011.
    • Recent Trend : falling falling trend
    • Recent AAPC : -8.4
    Lee County6,10
    • Rate : The incidence rate is 12.6 with a 95% confidence interval from 7.2 to 21.0.
    • Average Annual Count : The count is 3.
    • Rate Period : The period for the rate is 2007-2011.
    • Recent Trend : stable stable trend
    • Recent AAPC : -15.1
    Cook County6,10
    • Rate : The incidence rate is 12.7 with a 95% confidence interval from 12.1 to 13.3.
    • Average Annual Count : The count is 368.
    • Rate Period : The period for the rate is 2007-2011.
    • Recent Trend : stable stable trend
    • Recent AAPC : -1.4
    Williamson County6,10
    • Rate : The incidence rate is 12.7 with a 95% confidence interval from 8.4 to 18.7.
    • Average Annual Count : The count is 6.
    • Rate Period : The period for the rate is 2007-2011.
    • Recent Trend : stable stable trend
    • Recent AAPC : 16
    Livingston County6,10
    • Rate : The incidence rate is 12.9 with a 95% confidence interval from 7.3 to 21.5.
    • Average Annual Count : The count is 3.
    • Rate Period : The period for the rate is 2007-2011.
    • Recent Trend : stable stable trend
    • Recent AAPC : 26.7
    Jackson County6,10
    • Rate : The incidence rate is 13.0 with a 95% confidence interval from 7.5 to 20.9.
    • Average Annual Count : The count is 4.
    • Rate Period : The period for the rate is 2007-2011.
    • Recent Trend : stable stable trend
    • Recent AAPC : -4.9
    Peoria County6,10
    • Rate : The incidence rate is 13.1 with a 95% confidence interval from 10.2 to 16.6.
    • Average Annual Count : The count is 14.
    • Rate Period : The period for the rate is 2007-2011.
    • Recent Trend : stable stable trend
    • Recent AAPC : -7.9
    Boone County6,10
    • Rate : The incidence rate is 13.4 with a 95% confidence interval from 8.0 to 21.0.
    • Average Annual Count : The count is 4.
    • Rate Period : The period for the rate is 2007-2011.
    • Recent Trend : stable stable trend
    • Recent AAPC : 7.3
    Winnebago County6,10
    • Rate : The incidence rate is 13.7 with a 95% confidence interval from 11.4 to 16.5.
    • Average Annual Count : The count is 24.
    • Rate Period : The period for the rate is 2007-2011.
    • Recent Trend : stable stable trend
    • Recent AAPC : -4.3
    Adams County6,10
    • Rate : The incidence rate is 14.3 with a 95% confidence interval from 9.5 to 20.7.
    • Average Annual Count : The count is 6.
    • Rate Period : The period for the rate is 2007-2011.
    • Recent Trend : stable stable trend
    • Recent AAPC : 2.6
    Stephenson County6,10
    • Rate : The incidence rate is 14.7 with a 95% confidence interval from 9.4 to 22.3.
    • Average Annual Count : The count is 5.
    • Rate Period : The period for the rate is 2007-2011.
    • Recent Trend : stable stable trend
    • Recent AAPC : 31.4
    Whiteside County6,10
    • Rate : The incidence rate is 15.0 with a 95% confidence interval from 9.9 to 22.1.
    • Average Annual Count : The count is 6.
    • Rate Period : The period for the rate is 2007-2011.
    • Recent Trend : falling falling trend
    • Recent AAPC : -9.3
    La Salle County6,10
    • Rate : The incidence rate is 15.4 with a 95% confidence interval from 11.4 to 20.3.
    • Average Annual Count : The count is 11.
    • Rate Period : The period for the rate is 2007-2011.
    • Recent Trend : stable stable trend
    • Recent AAPC : 0.8
    Franklin County6,10
    • Rate : The incidence rate is 15.5 with a 95% confidence interval from 9.7 to 24.1.
    • Average Annual Count : The count is 5.
    • Rate Period : The period for the rate is 2007-2011.
    • Recent Trend : stable stable trend
    • Recent AAPC : -5.2
    McHenry County6,10
    • Rate : The incidence rate is 15.6 with a 95% confidence interval from 12.9 to 18.7.
    • Average Annual Count : The count is 24.
    • Rate Period : The period for the rate is 2007-2011.
    • Recent Trend : stable stable trend
    • Recent AAPC : 4.3
    Vermilion County6,10
    • Rate : The incidence rate is 15.8 with a 95% confidence interval from 11.3 to 21.7.
    • Average Annual Count : The count is 8.
    • Rate Period : The period for the rate is 2007-2011.
    • Recent Trend : stable stable trend
    • Recent AAPC : 10.4
    Marion County6,10
    • Rate : The incidence rate is 15.8 with a 95% confidence interval from 9.2 to 25.4.
    • Average Annual Count : The count is 4.
    • Rate Period : The period for the rate is 2007-2011.
    • Recent Trend : stable stable trend
    • Recent AAPC : -3.7
    Grundy County6,10
    • Rate : The incidence rate is 15.9 with a 95% confidence interval from 9.5 to 24.9.
    • Average Annual Count : The count is 4.
    • Rate Period : The period for the rate is 2007-2011.
    • Recent Trend : stable stable trend
    • Recent AAPC : 0
    Woodford County6,10
    • Rate : The incidence rate is 16.6 with a 95% confidence interval from 9.9 to 26.4.
    • Average Annual Count : The count is 4.
    • Rate Period : The period for the rate is 2007-2011.
    • Recent Trend : stable stable trend
    • Recent AAPC : 13.8
    Effingham County6,10
    • Rate : The incidence rate is 16.7 with a 95% confidence interval from 9.6 to 27.2.
    • Average Annual Count : The count is 3.
    • Rate Period : The period for the rate is 2007-2011.
    • Recent Trend : stable stable trend
    • Recent AAPC : 11.9
    Fulton County6,10
    • Rate : The incidence rate is 18.1 with a 95% confidence interval from 11.3 to 28.0.
    • Average Annual Count : The count is 5.
    • Rate Period : The period for the rate is 2007-2011.
    • Recent Trend : stable stable trend
    • Recent AAPC : -0.2
    Coles County6,10
    • Rate : The incidence rate is 19.8 with a 95% confidence interval from 13.1 to 28.8.
    • Average Annual Count : The count is 6.
    • Rate Period : The period for the rate is 2007-2011.
    • Recent Trend : stable stable trend
    • Recent AAPC : -9.4
    DeKalb County6,10
    • Rate : The incidence rate is 19.9 with a 95% confidence interval from 14.4 to 26.7.
    • Average Annual Count : The count is 9.
    • Rate Period : The period for the rate is 2007-2011.
    • Recent Trend : stable stable trend
    • Recent AAPC : -10.8
    Alexander County6,10
    • Rate : *
    • Average Annual Count : *
    • Rate Period : *
    • Recent Trend : *
    • Recent AAPC : *
    Bond County6,10
    • Rate : *
    • Average Annual Count : *
    • Rate Period : *
    • Recent Trend : *
    • Recent AAPC : *
    Brown County6,10
    • Rate : *
    • Average Annual Count : *
    • Rate Period : *
    • Recent Trend : *
    • Recent AAPC : *
    Bureau County6,10
    • Rate : *
    • Average Annual Count : *
    • Rate Period : *
    • Recent Trend : *
    • Recent AAPC : *
    Calhoun County6,10
    • Rate : *
    • Average Annual Count : *
    • Rate Period : *
    • Recent Trend : *
    • Recent AAPC : *
    Carroll County6,10
    • Rate : *
    • Average Annual Count : *
    • Rate Period : *
    • Recent Trend : *
    • Recent AAPC : *
    Cass County6,10
    • Rate : *
    • Average Annual Count : *
    • Rate Period : *
    • Recent Trend : *
    • Recent AAPC : *
    Christian County6,10
    • Rate : *
    • Average Annual Count : *
    • Rate Period : *
    • Recent Trend : *
    • Recent AAPC : *
    Clark County6,10
    • Rate : *
    • Average Annual Count : *
    • Rate Period : *
    • Recent Trend : *
    • Recent AAPC : *
    Clay County6,10
    • Rate : *
    • Average Annual Count : *
    • Rate Period : *
    • Recent Trend : *
    • Recent AAPC : *
    Clinton County6,10
    • Rate : *
    • Average Annual Count : *
    • Rate Period : *
    • Recent Trend : *
    • Recent AAPC : *
    Crawford County6,10
    • Rate : *
    • Average Annual Count : *
    • Rate Period : *
    • Recent Trend : *
    • Recent AAPC : *
    Cumberland County6,10
    • Rate : *
    • Average Annual Count : *
    • Rate Period : *
    • Recent Trend : *
    • Recent AAPC : *
    De Witt County6,10
    • Rate : *
    • Average Annual Count : *
    • Rate Period : *
    • Recent Trend : *
    • Recent AAPC : *
    Douglas County6,10
    • Rate : *
    • Average Annual Count : *
    • Rate Period : *
    • Recent Trend : *
    • Recent AAPC : *
    Edgar County6,10
    • Rate : *
    • Average Annual Count : *
    • Rate Period : *
    • Recent Trend : *
    • Recent AAPC : *
    Edwards County6,10
    • Rate : *
    • Average Annual Count : *
    • Rate Period : *
    • Recent Trend : *
    • Recent AAPC : *
    Fayette County6,10
    • Rate : *
    • Average Annual Count : *
    • Rate Period : *
    • Recent Trend : *
    • Recent AAPC : *
    Ford County6,10
    • Rate : *
    • Average Annual Count : *
    • Rate Period : *
    • Recent Trend : *
    • Recent AAPC : *
    Gallatin County6,10
    • Rate : *
    • Average Annual Count : *
    • Rate Period : *
    • Recent Trend : *
    • Recent AAPC : *
    Greene County6,10
    • Rate : *
    • Average Annual Count : *
    • Rate Period : *
    • Recent Trend : *
    • Recent AAPC : *
    Hamilton County6,10
    • Rate : *
    • Average Annual Count : *
    • Rate Period : *
    • Recent Trend : *
    • Recent AAPC : *
    Hancock County6,10
    • Rate : *
    • Average Annual Count : *
    • Rate Period : *
    • Recent Trend : *
    • Recent AAPC : *
    Hardin County6,10
    • Rate : *
    • Average Annual Count : *
    • Rate Period : *
    • Recent Trend : *
    • Recent AAPC : *
    Henderson County6,10
    • Rate : *
    • Average Annual Count : *
    • Rate Period : *
    • Recent Trend : *
    • Recent AAPC : *
    Iroquois County6,10
    • Rate : *
    • Average Annual Count : *
    • Rate Period : *
    • Recent Trend : stable stable trend
    • Recent AAPC : -2.5
    Jasper County6,10
    • Rate : *
    • Average Annual Count : *
    • Rate Period : *
    • Recent Trend : *
    • Recent AAPC : *
    Jefferson County6,10
    • Rate : *
    • Average Annual Count : *
    • Rate Period : *
    • Recent Trend : *
    • Recent AAPC : *
    Jersey County6,10
    • Rate : *
    • Average Annual Count : *
    • Rate Period : *
    • Recent Trend : *
    • Recent AAPC : *
    Jo Daviess County6,10
    • Rate : *
    • Average Annual Count : *
    • Rate Period : *
    • Recent Trend : *
    • Recent AAPC : *
    Johnson County6,10
    • Rate : *
    • Average Annual Count : *
    • Rate Period : *
    • Recent Trend : *
    • Recent AAPC : *
    Lawrence County6,10
    • Rate : *
    • Average Annual Count : *
    • Rate Period : *
    • Recent Trend : *
    • Recent AAPC : *
    Logan County6,10
    • Rate : *
    • Average Annual Count : *
    • Rate Period : *
    • Recent Trend : *
    • Recent AAPC : *
    Marshall County6,10
    • Rate : *
    • Average Annual Count : *
    • Rate Period : *
    • Recent Trend : *
    • Recent AAPC : *
    Mason County6,10
    • Rate : *
    • Average Annual Count : *
    • Rate Period : *
    • Recent Trend : *
    • Recent AAPC : *
    Massac County6,10
    • Rate : *
    • Average Annual Count : *
    • Rate Period : *
    • Recent Trend : *
    • Recent AAPC : *
    McDonough County6,10
    • Rate : *
    • Average Annual Count : *
    • Rate Period : *
    • Recent Trend : stable stable trend
    • Recent AAPC : 4.5
    Menard County6,10
    • Rate : *
    • Average Annual Count : *
    • Rate Period : *
    • Recent Trend : *
    • Recent AAPC : *
    Mercer County6,10
    • Rate : *
    • Average Annual Count : *
    • Rate Period : *
    • Recent Trend : *
    • Recent AAPC : *
    Monroe County6,10
    • Rate : *
    • Average Annual Count : *
    • Rate Period : *
    • Recent Trend : *
    • Recent AAPC : *
    Montgomery County6,10
    • Rate : *
    • Average Annual Count : *
    • Rate Period : *
    • Recent Trend : *
    • Recent AAPC : *
    Morgan County6,10
    • Rate : *
    • Average Annual Count : *
    • Rate Period : *
    • Recent Trend : falling falling trend
    • Recent AAPC : -19.8
    Moultrie County6,10
    • Rate : *
    • Average Annual Count : *
    • Rate Period : *
    • Recent Trend : *
    • Recent AAPC : *
    Perry County6,10
    • Rate : *
    • Average Annual Count : *
    • Rate Period : *
    • Recent Trend : *
    • Recent AAPC : *
    Piatt County6,10
    • Rate : *
    • Average Annual Count : *
    • Rate Period : *
    • Recent Trend : *
    • Recent AAPC : *
    Pike County6,10
    • Rate : *
    • Average Annual Count : *
    • Rate Period : *
    • Recent Trend : *
    • Recent AAPC : *
    Pope County6,10
    • Rate : *
    • Average Annual Count : *
    • Rate Period : *
    • Recent Trend : *
    • Recent AAPC : *
    Pulaski County6,10
    • Rate : *
    • Average Annual Count : *
    • Rate Period : *
    • Recent Trend : *
    • Recent AAPC : *
    Putnam County6,10
    • Rate : *
    • Average Annual Count : *
    • Rate Period : *
    • Recent Trend : *
    • Recent AAPC : *
    Randolph County6,10
    • Rate : *
    • Average Annual Count : *
    • Rate Period : *
    • Recent Trend : *
    • Recent AAPC : *
    Richland County6,10
    • Rate : *
    • Average Annual Count : *
    • Rate Period : *
    • Recent Trend : *
    • Recent AAPC : *
    Saline County6,10
    • Rate : *
    • Average Annual Count : *
    • Rate Period : *
    • Recent Trend : *
    • Recent AAPC : *
    Schuyler County6,10
    • Rate : *
    • Average Annual Count : *
    • Rate Period : *
    • Recent Trend : *
    • Recent AAPC : *
    Scott County6,10
    • Rate : *
    • Average Annual Count : *
    • Rate Period : *
    • Recent Trend : *
    • Recent AAPC : *
    Shelby County6,10
    • Rate : *
    • Average Annual Count : *
    • Rate Period : *
    • Recent Trend : *
    • Recent AAPC : *
    Stark County6,10
    • Rate : *
    • Average Annual Count : *
    • Rate Period : *
    • Recent Trend : *
    • Recent AAPC : *
    Union County6,10
    • Rate : *
    • Average Annual Count : *
    • Rate Period : *
    • Recent Trend : *
    • Recent AAPC : *
    Wabash County6,10
    • Rate : *
    • Average Annual Count : *
    • Rate Period : *
    • Recent Trend : *
    • Recent AAPC : *
    Warren County6,10
    • Rate : *
    • Average Annual Count : *
    • Rate Period : *
    • Recent Trend : *
    • Recent AAPC : *
    Washington County6,10
    • Rate : *
    • Average Annual Count : *
    • Rate Period : *
    • Recent Trend : *
    • Recent AAPC : *
    Wayne County6,10
    • Rate : *
    • Average Annual Count : *
    • Rate Period : *
    • Recent Trend : *
    • Recent AAPC : *
    White County6,10
    • Rate : *
    • Average Annual Count : *
    • Rate Period : *
    • Recent Trend : *
    • Recent AAPC : *


    Notes:
    Created by statecancerprofiles.cancer.gov on 10/21/2014 9:34 am.
    Data for the United States does not include data from Nevada.
    State Cancer Registries may provide more current or more local data.
    † Incidence rates (cases per 100,000 population per year) are age-adjusted to the 2000 US standard population (19 age groups: <1, 1-4, 5-9, ... , 80-84, 85+). 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 1969-2012 US Population Data File is used for SEER and NPCR incidence rates.
    § The total count for the US (SEER+NPCR) may differ from the summation of the individual states reported in this table. The total uses data from the CDC's National Program of Cancer Registries Cancer Surveillance System (NPCR-CSS) January 2013 data submission for the following states: California, Kentucky, Louisiana, and New Jersey but data for those states when shown individually are sourced from the SEER November 2013 submission.
    * Data has been suppressed to ensure confidentiality and stability of rate estimates. Counts are suppressed if fewer than 16 cases were reported in a specific area-sex-race category.

    1 Source: CDC's National Program of Cancer Registries Cancer Surveillance System (NPCR-CSS) January 2014 data submission and SEER November 2013 submission.
    6 Source: State Cancer Registry and the CDC's National Program of Cancer Registries Cancer Surveillance System (NPCR-CSS) January 2014 data submission. State rates include rates from metropolitan areas funded by SEER.
    10 Source: Incidence data provided by the National Program of Cancer Registries (NPCR). EAPCs calculated by the National Cancer Institute using SEER*Stat. Rates are age-adjusted to the 2000 US standard population (19 age groups: <1, 1-4, 5-9, ... , 80-84,85+). Rates are for invasive cancer only (except for bladder cancer which is invasive and in situ) or unless otherwise specified. Population counts for denominators are based on Census populations as modified by NCI. The 1969-2012 US Population Data File is used with NPCR January 2014 data.

    Please note that the data comes from different sources. Due to different years of data availablility, most of the trends are AAPCs based on APCs but some are EAPCs calculated in SEER*Stat. Please refer to the source for each graph for additional information.

    Interpret Rankings provides insight into interpreting cancer incidence statistics. When the population size for a denominator is small, the rates may be unstable. A rate is unstable when a small change in the numerator (e.g., only one or two additional cases) has a dramatic effect on the calculated rate.

    Suppression is used to avoid misinterpretation when rates are unstable.