I can't replicate your problem in the High Sierra Gold Master, but you might check your View settings in Preview - particularly Zoom and Zoom to fit.
My Preview settings are apparently academic, because in addition to appearing incorrectly in Preview, the docs print incorrectly.
("Actual Size" and "Zoom to Fit" are checked, but greyed out, in Preview > View.)
More: I just found a Preview pref set for "Define 100% scale as: Size on screen equals size on printout", so "size on printout" apparently differs depending upon which way I initiate printing.