Its difficult to visualize your use case since your description is not concrete. It seems like a pie chart report (which displays by %) might be useful here since it allows drill down to the items in that category. For example, a record can possess a Hi, Med, or Low status and the pie chart would display the % of records in each status by overall number.
Your description however, indicates you are looking for a summary vs a chart solution so more clarification may be needed. To clarify, the All you have indicated above would be 100 %. When you expand that, you might get 3 rows : 50% Hi, 30% Med, and 20% Low (assuming you follow the example above) as opposed to the number of counts. And then you drill down into the individual status to find the records. Is this correct ? If not, please clarify.