Imagine that you are a government official in a local health department, in charge of an immunization program that provides free immunizations to all uninsured children in your county. The County Board of Supervisors (which is in charge of all county health care related matters, and funds your department) has asked you to justify your program's budget by demonstrating that your program has made significant progress over the past two years, increasing the immunization rates of low-income children in the county. You have baseline data from three years ago that shows the average immunization rate for children ages 0-17 was 65%. How would you demonstrate now that low-income children in your county on average have a significantly higher immunization rate than the baseline