Fix relative runtime ratios with an explicit reference

doc/hyperfine.1

@@ -118,6 +118,8 @@ not every time as would happen with the \fB\-\-prepare\fR option.
 .IP
 Benchmark \fICMD\fP as the reference for the relative comparison of results.
 If this option is not specified, the fastest command is used as the reference.
+In the command-sorted comparison and exported markup tables, values below 1
+indicate commands faster than the reference.
 .HP
 \fB\-\-reference\-name\fR \fINAME\fP
 .IP