The hurricane risk index is simply the product of the cumulative hurricane strikes per coastal county and the CDC Overall Social Vulnerability Index (SVI) for the given county. We normalize the hurricane strikes data to match the SVI data classification scheme (i.e., max value at 1); however, using the raw or normalized values of hurricane strikes has no impact on the spatial pattern of the risk index.  Therefore, a risk index of value 1 indicates the county has the highest hurricane strikes of all the counties and is the most vulnerable county in the nation according to the SVI index.  Because the analysis is over multiple states, we use the ‘United States’ SVI dataset at the county level.  Values of the index are unevenly distributed so we classify intervals using the Jenks method and the first break at 0.08 is roughly equal to the median index value.  For counties north of North Carolina, the low hurricane risk is most dependent on the low number of hurricane strikes.  The vast majority of the counties fall in the lowest risk category and any in the second lowest category are there because of high social vulnerability.