More precisely, the average fashion-conscious young Japanese woman who reads CanCam and responds to surveys with some degree of honesty, from a sample of 1,000 selected by an undisclosed method.
To save time for the Katakana-challenged, the key numbers are 78.4cm-60.6cm-85.6cm (31-24-34), with an average height of 158.2cm (5’2”). This is not the same as their stable of models, of course, who tend to be several inches taller and a bit curvier (based on some inadequate but visually appealing sampling I just did, which included the popular and delicious Ikumi Hisamatsu).
Incidentally, while browsing their stable, I noticed that CanCam’s numbers for 22-year-old Rikako Sakata (88-57-85) differed substantially from Wikipedia’s (80-58-80). Turns out nobody’s updated that part of her Wikipedia page since she was 16, which is surprising given how detail-oriented Japanese fans tend to be. Then again, maybe she’s simply too old for them now; they cared when she was 13 (65-54-70) and 15 (78-55-76), but not so much now. Amusing intermediate data point: a 2014 video date (83-58-79) I came across in my “research”.