in Sources/_TracingBenchmarkTools/DriverUtils.swift [641:652]
func quantiles(q: Int) -> [String] {
// See https://en.wikipedia.org/wiki/Quantile#Specialized_quantiles
let prefix = [
2: "MEDIAN", 3: "T", 4: "Q", 5: "QU", 6: "S", 7: "O", 10: "D",
12: "Dd", 16: "H", 20: "V", 33: "TT", 100: "P", 1000: "Pr",
][q, default: "\(q)-q"]
let base20 = "0123456789ABCDEFGHIJ".map { String($0) }
let index: (Int) -> String =
{ q == 2 ? "" : q <= 20 ? base20[$0] : String($0) }
let tail = (1 ..< q).map { prefix + index($0) } + ["MAX"]
return [withUnit("MIN")] + tail.map(c.delta ? withDelta : withUnit)
}