Heat Index

The U.S. has 50 states, and each state has individual counties, over 3000 total counties in the U.S. My online tool shows users where to obtain the latest COVID statistics for their State or County, lets them manually input the statistics, performs some risk analysis ofthe data for their given lifestyle variables, and allows them to compare their \"Target Area" with another area of interest, say another county, a State, NY City, the US, etc. I wish to devise a single-number index ("Heat Index\") so the user can quickly and easily visualize how their Target Area compares to the other area of interest. See the attached jpg. There are separate data sources for US Totals, State by State breakdown, and County by County breakdown. My app uses a separate data source for US totals, which is an aggregate of all the county [or state) data. So it stands to reason that the obvious numbers to compare one's Target Area to are "the rest of the cou ntry\" i.e. the US totals. Questions I have: 1] Because the \"US Totals\" are the aggregate of all US states {or counties] combined, the US Totals index should always be 100% (Le. should not deviate from the norm) when compared to a US state or county, right? The only time US Totals should be other than 100 would be if compared to other countries (such as yours]. correct? 21 Would the U5 Totals cases/hosp/deaths per 100000 represent the average of all the individual state [or county] totals combined? If so then we can base the heat index on a given Target Area's deviation from the average [US Totals), correct? And that means we are probably thinking in terms of Percentile Rank as index score, correct? 3] Given #2 above we would have Percentile Rank for each of three categories: cases. hospitalizations, deaths. Should the Heat Index simply average the three (Percentile Rank) scores or should the scores be weighted by statistic of greatest concern (for lack of a better term). For example I'm in Summit County, Ohio (with 3 Heat Index of 40.5] and looking to travel to Miami Beach (Dade County, Florida with 3 Heat Index of 62.3}. I'm mostly concerned about the i" of cases, as I would n't be hospitalized, and subsequently wouldn't die, if I f don't get infected by potential interaction with an infected Florida Resident