Vintage 60's Maxi Dress geometric green navy white 18 Retro

Retro 60's polyester maxi dress see measurements for size tag says 18 (vintage 18) but I think that was a smaller cut back then. no brand tag on the dress. it was my mothers from the late 60's. Excellent condition recently dry cleaned, stored in dress bag. Measurements seem to be closer to current 12/14 see conversation in the comments. I listed as 12/14 to be in the correct current sizing. Please go by the Measurements and please note the tag says 18, but size 18 in the 60's was cut much smaller than today's 18. chest 22" across Waist 17" across sweep 60" length 55" shoulder to hem sleeve 22" shoulder seem to bottom kelly green, navy and white, matched patterned seams, darted chest, wide sweep across bottom hem.