IIRC, McFarland's bonus was slot value for the 103rd overall pick, which is in the early-mid 3rd round. If signability weren't a constraint with him, he would have gone in the top 5ish rounds, I think. Maybe Patrick can provide a better answer on that. How did 18 get more than twice that of 6 through 10? Much more so than the NFL or NBA drafts, players drop in the MLB draft because they're regarded as tough signs. A lot of this has to do with the lack of hard contract slotting in the baseball draft. First round talent can drop way past even the 18th round.