Height is a proxy for the winning builder's real build time: every builder starts its VDF at roughly the same moment, and a block's timestamp is stamped the instant its builder finishes, so this is (start delay + build time), not the literal number. The vertical axis is scaled to the actual data range so ordinary variation is visible, rather than a fixed scale a single spike would flatten; hollow points are pinned to the top/bottom edge because their real value falls outside that range (hover for the exact number). They're excluded from the odds figure above but still plotted, nothing is dropped from the chart itself.