SCALP HAIR LENGTH 371 Table IV Anatomical Measurements (cm) From Crown of Six Panelists* Sex F F F M M M Avge Range Height 163 170 158 191 178 185 174 158 to 191 Shoulders 25.4 27.9 27.9 30.5 30.5 33 29.2 25.4 to 33 Bottom shoulder blades 45.7 48.3 45.7 45.7 48.3 50.8 47.4 45.7 to 50.8 Waist 61 63.5 61 73.7 68.6 76.2 67.3 61 to 76.2 Buttocks 91.4 94 88.9 101.6 104.1 106.7 97.8 88.9 to 106.7 Knees 119.4 124.5 116.8 142.2 132 134.6 128.3 116.8 to 142.2 Ankles 152.4 160 147.3 180.3 170.2 172.7 163.8 147.3 to 180.3 * From frontal area add 12.7 cm. The actual length of the hair pulled taut will always be longer than the above measurements the difference depends on the amount of curvature in the hair. Assume about a 5% additional length for taut hair, although it will be longer than 5% if the hair is very curly or if it is braided. If the hair is very straight, the taut length may be less than an additional 5%. Table V Anatomical Sites and Approximate Hair Length Rounded Off to Nearest Centimeter From B Approximate Approximate Approximate From A range midpoint* midpoint + 5%** Shoulder-length 25 to 33 35 to 43 25 to 43 34 _+ 9 Lower-shoulder-blade-length 46 to 51 56 to 61 46 to 61 53.5 _+ 8 Waist-length 61 to 76 71 to 86 61 to 86 73.5 _+ 15 Buttocks-length 89 to 107 99 to 117 89 to 117 103 _+ 14 Knee-length 117 to 142 127 to 152 117 to 152 134.5 _+ 18 Ankle-length 147 to 180 157 to 190 147 to 190 168.5 _+ 22 36-+9 56-+8 77-+ 15 108 -+ 14 141 -+ 18 177 -+ 22 A is the frontal area, and B represents the crown area. A = B + 10.2 cm (4 inches). * Represents the approximate length of hair as it hangs free from the midscalp. ** Approximates the taut length of hair from the midscalp. See explanation in Table V. line (A) was used to estimate the approximate numbers of people in the USA at several hair lengths within and beyond the limits of the graph: Y = 5.693 - 0.0945X (A) Y = In% of population, and X = hair length in centimeters. R 2 = 0.998 and is highly significant. For all calculations from this equation, one should use either the average lengths from the anatomical sites of Table IV or if other individual lengths are used, one should choose lengths at least as far apart as the plus or minus values for the averages listed in Table IV otherwise the added percentages will exceed 100%. Extrapolation of this line, Figure 2, permits us to estimate percentages and numbers of people in the USA with even longer hair lengths. We used 183 cm (six feet) as the cutoff point for extrapolation, based on information provided by Figure 3 and described later in this paper. In the theme park studies, no person was observed with hair longer than buttocks- length. However, hair much longer than that exists and has been reported from many different sources (3-8). Hair down to the ankles has been observed for many persons, including the beautiful hair of the entertainer Crystal Gayle (see Figure 4). Equation A

372 JOURNAL OF COSMETIC SCIENCE 0.0-- -2.5 - - -5.0 ß, 25 i i I 50 75 1 O0 Hair Length in Centimeters Figure 2. Plot of the natural logarithm of the percentage of the population versus hair length (in centi- meters). suggests that 9.6 x 10-6% of the population has hair 183 cm long), or about 21 people in the USA, and that about 73 people in the USA have hair that reaches to their ankles (free-hanging length of approximately 168 + 22 cm) (see Table VI). Therefore, a lit- erature search was conducted to try to obtain an indication of the relative numbers of people known to have hair ankle-length or longer (free-hanging lengths of approxi- mately 168 + 22 cm and longer). Table VII provides a summary of persons with very long hair, and that hair has been categorized into three groups by length. Among the sources for this tabulation are the Guiness Book of World Records from 1996 and 1999 (5,6), and a long-hair website by Frank Pflonissen (7). Other sources are an internet article by Sutin Wannabovorn (8)