Understanding Trends Over Time

Examining changes in health outcomes over time can provide an overall sense of community progress toward health. Trends in health factors can inform specific health programs and may reflect the impact of local efforts. 

Trend graphs

For each measure with trend data available, a detailed trend graph can be viewed by clicking on the graph icons in the county snapshot. Each graph icon is color-coded to communicate the direction of the trend:

The county value is trending worse for this measure 

The county value shows no significant trend 
The county value is trending better for this measure 
Icon of a trend graph in gray indicating additional information is needed to assess the trend
Additional information is needed to interpret the trend for this measure

These questions can help guide interpretation of the trend graphs: 

  1. Is the county value increasing, decreasing, or staying the same over time?
  2. Is the county trend better, worse, or similar to the state trend?
  3. Is the county trend better, worse, or similar to the national trend?
  4. What worldwide, national, or local events occurred during this time period that may have impacted the measure?


The County Health Rankings data come from over 30 different sources, each with unique methods for data collection and processing which impact the feasibility and reliability of comparisons over time. County Health Rankings produces trend graphs where feasible and meaningful.

Trend data is currently available for:

  • Thirteen ranked measures: Premature death, Alcohol-impaired driving deaths, Sexually transmitted infections, Uninsured, Primary care physicians, Dentists, Preventable hospital stays, Mammography screening, Flu vaccinations, Unemployment, Children in poverty, Violent crime, and Air pollution; and
  • Three additional measures: Uninsured adults, Uninsured children, and School funding adequacy.  

Additional guidance about how to interpret the trend graphs to understand progress in your community can be found here.