Key Points
- The American Family is changing in response to the pressures and opportunities facing young individuals.
- Many children today are being raised by single parents, which is associated with a lower transmission of skills to succeeding generations.
- Technological advances and public provision of social protection benefits appear to be contributing to the decline of the nuclear family.
Emergent Changes in American Demography and Social Organization
Introduction
The term “demographic change” has become almost synonymous with “population aging” today, but it is actually much broader and multidimensional. The term encompasses changes in marriage rates, mating patterns, divorce, and living arrangements; shifts in fertility choices and timing; changes in immigration; improvements in mortality rates; and shifts in health and wellness patterns (smoking, nutrition, and exercise), educational attainment, labor force participation, and retirement. These changes are infusing seemingly permanent transformations in the forms of social organization even at the most basic level of “the family.”
The form of social organization has been evolving during the postwar period. This is the process of family formation and dissolution driven by technological advancements and economic opportunities that induce changes in social organization and cultural norms. They are reflected in trends in social institutions that govern family formation and dissolution across successive age-cohorts: marriage rates, mating patterns across socioeconomic groups, divorce rates and patterns, out-of-wedlock births, and frequency of single-parenthood.
The dilution of family ties is likely to affect the degree of skill and knowledge transmission to the next generation of workers. It is now widely accepted among sociologists and economists that children raised by single parents are less likely to succeed academically, more prone to engage in riskier activities, and less likely to realize positive market outcomes during adulthood.1 Indeed, perceptions of worsening economic prospects for younger American generations are already provoking calls for the government to play a larger role in children’s upbringing and education, even during early childhood.
Economics of the Family
The family is the most basic social unit within which the young are nurtured into responsible and self-supporting adults. Family formation might be motivated by the “survival instinct” – the desire to preserve and extend one’s lineage. Traditionally, communities with strong family values have been associated with strong social cohesion, cultural identity, and economic progress.
The economic approach to analyzing social structures views families as a means for achieving individuals’ economic goals. The form of “the family” can only promote social cohesion and economic progress if it is best suited to fulfill the demands for various types of services and exchange that are mutually valued by the individuals in a family. Those exchanges include physical security, close community, insurance against future economic uncertainty, sustenance during old age, a nurturing environment for children, and the transfer of cognitive and non-cognitive skills to one’s offspring.2 All of these functions, accomplished through family formation, have help to preserve and extend the heredity of individuals for many centuries.
Under this view, for any form of social organization to survive, it must continue to effectively deliver the services that its constituents seek. Social organization through families survived for many millennia partly because it was the most efficient way of delivering the key services needed for survival, protection, material and spiritual advancement, and generational succession.
Then, does the observed trend toward fragmentation of the family as the main form of social organization mean that it has become less efficient at delivering those services? Alternatively, have other means of acquiring those services emerged and become stronger?
Long Run Trends
Family fragmentation has been ongoing for many decades in the United States. There are many and changing reasons for this phenomenon. Joint living within extended families was the norm in many agricultural communities because arduous domestic and farm work compelled considerable division of labor and interdependence among extended family members.
The post-Civil War industrialization, technological change, and globalization meant greater urbanization and worker mobility leading to the dissolution of extended families. But those changes also meant the erosion of family support systems that protected individuals from economic misfortunes such as job loss, disability, unanticipated longevity (without means of economic support), divorce, dependency, and widowhood.
Post-World-War-II technological advancements also reduced exertional requirements in domestic work and permitted greater control over the timing of childbirth. These changes have allowed women to enter market production, contributing to economic growth and a greater sense of self-determination.
But those technological changes also led to greater specialization and increased business cycle volatility. The experience of the Great Depression of the 1930s was a watershed event: It prompted rapid growth in the entitlement-welfare state with the enactment of Social Security. That legislation is often described as America's "social response" to counter increased economic uncertainties for all individuals.
Over time, growth in publicly provided social protections have appeared to further erode the need for intra-family, inter-gender, and inter-generational risk sharing through family based social structures. Today, federal and state social insurance programs exist to insure individuals against income losses from life and health contingencies, benefiting retirees, the disabled, survivors, dependents, divorcees, students, children, and the poor. While such expansions of public safety net programs pools risk across households, it has also reduced family dependencies and the need for securing such protections through the family.
Figure 1: Household Composition of People Ages 18 and Older
Source: Decennial Census and the Current Population Survey.
With rising divorce rates, younger individuals may consider marriage to be less secure and seek to insure economic autonomy and independence before marrying. In this process, younger generations may rationally consider marriage as a poor bargain. In contrast, bachelorhood may be associated with greater social and financial freedom as, indeed, many national surveys confirm.3 Finally, the decline in marriage as a functional social institution may become self-perpetuating as younger generations emulate their elders’ behavior of altering their marital status multiple times.
Recent Trends
Figure 2: Population Shares of Married Males and Females by Age: 1988, 2000, and 2012
Source: PWBM calculations from the Current Population Survey.
Family formation through marriage is declining. Figure 2 shows a steady decline in the frequency of married individuals in the population. For both males and females, the decline is consistent and significant across all adults under 60 years. The marriage frequency profile declines with age at older ages, but it has shifted upward over time as declining mortality reduced the incidence of widowhood during the last two decades. The marriage decline among younger adults appears to be consistent with increased control over the timing of childbirth and potentially changing cultural norms away from marriage as a prerequisite for parenthood. Whether marriages will become insignificant in the future remains an open question. More important, however, is the efficacy of emergent social structures in preparing younger generations to face future economic challenges.
Figure 3: Population Shares of Single Males and Females by Age: 1988, 2000, and 2012
Source: PWBM calculations from the Current Population Survey.
Figure 3 shows that today’s youth, on average, are also tying the knot much later in life than their counterparts in the past. In 1960, most women married at the age of 20 and men at 23. Today, however, women marry, on average, at the age of 27 and men at 29.4 As young adults marry, the age-specific percentage of single individuals declines rapidly so that singles make up just 10 percent of those in their mid-thirties. Figure 3 shows that the rate of decline by age of the share of singles is shallower in 2012 compared to 1988, especially at young ages. It means that rate of transition into married status has gradually slowed during the last two decades, mirroring the decline in marriage rates.
Figure 4: Female Single Parents in 2010: Ages 15-20
Source: PWBM calculations from the Current Population Survey, 2010.
Figure 4 shows that black and Hispanic households are substantially more likely to be headed by a single female. From 1890 to 1930, black men were more likely to be married than white men. By 1960, this trend reversed and the change gained momentum after 1980.5 A number of studies attempt to examine the cause of this change, ranging from a decline in manufacturing, inequality and changes in social norms.6
Family Settings for Today’s Children
Relative to the past, today’s children are more likely to be raised by a single parent. According to data from the U.S. Census Bureau, approximately 87 percent of children resided with both parents during 1960s. By 2008, that number declined to 64 percent. At the same time, the number of children born to unmarried women increased from 5 percent to 41 percent.
The frequency of single-headed families among today’s adults has increased compared to the past – a shift that is shared by all racial groups. As shown in Figure 5, about 80 percent of children reside in white dual-headed families and 40 percent among black dual-headed families. Between 50 and 60 percent of Hispanic and Asian and Other children reside in dual-headed families.
Figure 5: Age-Specific Shares of Children in Single-Headed Families
Source: PWBM calculations from the Current Population Survey, 1988, 2000, and 2012.
From 1990 to 2010, the largest decline in children raised in married families is among the groups categorized as Asian and Other. Interestingly, the ratio of single-without-children and single-parenthood has not significantly changed for this group, suggesting that this decline reflects reduced fertility among married females during the last two decades. Among all races, in general, more children are still raised among families with two parents rather than one.
Conclusion
Social organization via two-parent married families is on a downward trend. As a result, more children are being raised in single-parent families. These demographic changes hold important implications, not only for economic prosperity of younger generations; they also threaten to undermine social support systems for older generations. If recent trends in social organization continue and lead to slower productivity growth, government revenues and the financial base for public social protection programs such as Social Security, Medicare, Medicaid, and SSI may become seriously compromised.
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Sara McLanahan and Christine Percheski (2008), “Family Structure and the Reproduction of Inequalities.” Annual Review of Sociology (34): 257-276. David Autor and Melanie Wasserman (2013), “Wayward Sons: The Emerging Gender Gap in Labor Markets and Education.” Third Way, Washington, DC. ↩
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Economist Gary Becker initiated the concept of “family economics” where family formation and childbearing could be explained in terms of economic choices. He argued that people tend to make family choices based on whether they can improve their own welfare. ↩
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A Pew Research Center Survey asked respondents for their views on whether society is better off if people make marriage and having children a priority, or society is just as well off if people have priorities other than marriage and children. Some 46% of adults chose the first statement, while 50% chose the second. See: http://www.pewsocialtrends.org/2014/09/24/record-share-of-americans-have-never-married/#fn-19804-4 ↩
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U.S. Census Bureau, Current Population Survey, March and Annual Social and Economic Supplements, 2015 and earlier. See: https://www.census.gov/data/tables/time-series/demo/families/marital.html. ↩
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See “Historical Marriage Trends from 1890 - 2010: A Focus on Race Differences.” Presentation by a U.S. Census statistical team (Diana B. Elliott, Kristy Krivickas, Matthew W. Brault, and Rose M. Kreide) at the Annual Meetings of the Population Association of America, San Francisco, CA, May 3 - 5, 2010. ↩
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See, for example, Kathryn Edin and Maria Kefalas (2005). Promises I Can Keep. University of California Press. ↩
,1960,1990,2008 Living with spouse & children,47,33,27 Living alone,6,12,14 Living with children no spouse,6,8,10
Age,1988,2000,2012 18,0.0059,0,0.005 19,0.0181,0.0105,0.0053 20,0.0473,0.0217,0.0144 21,0.0465,0.0389,0.0236 22,0.0872,0.0632,0.0341 23,0.1158,0.0994,0.0485 24,0.1579,0.1098,0.0788 25,0.177,0.1156,0.0955 26,0.2077,0.1697,0.1163 27,0.2254,0.1977,0.1422 28,0.25,0.2283,0.1564 29,0.277,0.2143,0.184 30,0.2632,0.2513,0.2163 31,0.2926,0.2537,0.2009 32,0.2927,0.2834,0.2319 33,0.2947,0.2642,0.2365 34,0.2892,0.2679,0.2417 35,0.3173,0.2946,0.2549 36,0.3264,0.2667,0.2629 37,0.3226,0.2788,0.2746 38,0.3204,0.293,0.2872 39,0.3161,0.3053,0.297 40,0.3598,0.2913,0.28 41,0.369,0.2917,0.2896 42,0.3696,0.3136,0.2952 43,0.3475,0.3241,0.2814 44,0.3615,0.3241,0.3069 45,0.3643,0.3396,0.295 46,0.3651,0.3172,0.2974 47,0.359,0.3263,0.3014 48,0.3613,0.3466,0.2982 49,0.3796,0.314,0.2905 50,0.3391,0.3771,0.304 51,0.3846,0.3669,0.3198 52,0.3925,0.3653,0.3204 53,0.37,0.3758,0.3317 54,0.4063,0.3719,0.3283 55,0.3878,0.3462,0.3286 56,0.4059,0.3413,0.3073 57,0.36,0.368,0.3209 58,0.4095,0.3364,0.3172 59,0.3654,0.3514,0.3425 60,0.3738,0.3585,0.3392 61,0.3838,0.3636,0.3314 62,0.3776,0.3824,0.3269 63,0.3714,0.3763,0.3072 64,0.3684,0.3478,0.3355 65,0.3663,0.3438,0.3571 66,0.3673,0.369,0.3333 67,0.3696,0.3523,0.3534 68,0.3765,0.3529,0.3613 69,0.3373,0.3452,0.3415 70,0.3086,0.3256,0.3426 71,0.3649,0.3494,0.3608 72,0.3194,0.3043,0.3529 73,0.3582,0.3117,0.3529 74,0.2951,0.3506,0.3125 75,0.3125,0.3117,0.3067 76,0.3091,0.2958,0.3333 77,0.2593,0.2857,0.3594 78,0.3182,0.2794,0.3065 79,0.2564,0.2857,0.3175
Age,1988,2000,2012 18,0.0296,0.0213,0.005 19,0.0542,0.0368,0.0107 20,0.0947,0.0543,0.0239 21,0.1221,0.0833,0.0425 22,0.1686,0.1149,0.078 23,0.1789,0.1404,0.0825 24,0.2263,0.1618,0.1182 25,0.2392,0.1908,0.1256 26,0.2609,0.2242,0.1628 27,0.2676,0.2442,0.1814 28,0.2885,0.2554,0.2227 29,0.3099,0.2667,0.2406 30,0.3026,0.2667,0.2308 31,0.2969,0.2935,0.2511 32,0.3122,0.2995,0.2657 33,0.3285,0.3005,0.2759 34,0.3235,0.3158,0.2607 35,0.3221,0.2991,0.2647 36,0.3109,0.3067,0.2887 37,0.3226,0.3186,0.2591 38,0.337,0.3116,0.2979 39,0.3563,0.3097,0.2871 40,0.3333,0.3,0.3 41,0.3571,0.3241,0.2941 42,0.3261,0.3227,0.3048 43,0.3546,0.3241,0.3266 44,0.3615,0.3194,0.3175 45,0.3429,0.3255,0.31 46,0.3571,0.3333,0.3179 47,0.3504,0.3421,0.3158 48,0.3613,0.3239,0.2982 49,0.3426,0.3372,0.319 50,0.3739,0.3371,0.3304 51,0.3654,0.3373,0.3153 52,0.3645,0.3234,0.3107 53,0.35,0.3248,0.3116 54,0.3646,0.3306,0.3182 55,0.3673,0.3308,0.319 56,0.3465,0.3492,0.3281 57,0.38,0.336,0.3155 58,0.3429,0.3455,0.328 59,0.3654,0.3514,0.3149 60,0.3551,0.3302,0.3041 61,0.3636,0.3232,0.3081 62,0.3367,0.3137,0.3141 63,0.3238,0.3226,0.3012 64,0.3263,0.3478,0.3158 65,0.3168,0.3125,0.3052 66,0.2959,0.2857,0.3083 67,0.3152,0.3068,0.2931 68,0.2941,0.2941,0.2857 69,0.3133,0.3095,0.3089 70,0.284,0.3023,0.2685 71,0.2703,0.2651,0.2784 72,0.25,0.2899,0.2941 73,0.2388,0.2727,0.2824 74,0.2459,0.2208,0.2875 75,0.2188,0.2597,0.32 76,0.1818,0.2394,0.2667 77,0.2037,0.2063,0.25 78,0.1591,0.2206,0.2581 79,0.2051,0.1786,0.2222
Age,1988,2000,2012 18,0.4556,0.4574,0.4677 19,0.4398,0.4263,0.4599 20,0.3905,0.3913,0.4211 21,0.3605,0.35,0.4057 22,0.2965,0.3218,0.3854 23,0.2526,0.2807,0.335 24,0.2211,0.2659,0.3103 25,0.1914,0.2312,0.2563 26,0.1643,0.1939,0.2419 27,0.1455,0.1686,0.2108 28,0.1442,0.1522,0.1896 29,0.1268,0.1476,0.1651 30,0.0965,0.1231,0.1442 31,0.1048,0.1045,0.1279 32,0.0878,0.107,0.1208 33,0.0773,0.0933,0.1084 34,0.0784,0.0909,0.109 35,0.0721,0.0982,0.1029 36,0.0777,0.0889,0.0928 37,0.0645,0.0885,0.1036 38,0.0718,0.0837,0.0957 39,0.069,0.1062,0.0891 40,0.0688,0.0957,0.09 41,0.0774,0.0972,0.1131 42,0.0942,0.1,0.1 43,0.078,0.0926,0.1106 44,0.0923,0.1019,0.1111 45,0.1071,0.0991,0.125 46,0.0952,0.1398,0.1231 47,0.1111,0.1105,0.134 48,0.1008,0.1364,0.1284 49,0.1019,0.1337,0.1333 50,0.113,0.1429,0.1498 51,0.1058,0.1361,0.1441 52,0.1121,0.1557,0.1602 53,0.12,0.172,0.1558 54,0.1146,0.1405,0.1566 55,0.1122,0.1462,0.1524 56,0.1287,0.1587,0.1667 57,0.14,0.152,0.1765 58,0.1429,0.1727,0.1774 59,0.1442,0.1712,0.1713 60,0.1495,0.1698,0.1871 61,0.1515,0.1717,0.1919 62,0.1735,0.1569,0.1987 63,0.2,0.172,0.2108 64,0.1895,0.1848,0.1974 65,0.2079,0.2083,0.1948 66,0.2143,0.2024,0.2083 67,0.2174,0.2045,0.2155 68,0.2353,0.2235,0.2269 69,0.253,0.2143,0.2114 70,0.284,0.2442,0.2407 71,0.2703,0.2771,0.2371 72,0.3056,0.2899,0.2353 73,0.3134,0.2727,0.2235 74,0.3443,0.3247,0.2625 75,0.3438,0.2857,0.2667 76,0.3636,0.338,0.28 77,0.4074,0.3651,0.3125 78,0.4318,0.3824,0.3226 79,0.4359,0.3929,0.3492
Age,1988,2000,2012 18,0.497,0.484,0.4826 19,0.4639,0.4895,0.4759 20,0.4201,0.462,0.5024 21,0.4128,0.45,0.4575 22,0.3953,0.4138,0.4195 23,0.3632,0.3626,0.432 24,0.3105,0.3353,0.3744 25,0.2967,0.3237,0.3819 26,0.2609,0.2848,0.3442 27,0.2441,0.2616,0.3039 28,0.1923,0.2228,0.2559 29,0.1831,0.1905,0.2264 30,0.1886,0.1949,0.2356 31,0.1703,0.1891,0.21 32,0.1463,0.1551,0.2029 33,0.1401,0.171,0.1773 34,0.1373,0.1388,0.1564 35,0.1394,0.1563,0.1716 36,0.1192,0.1556,0.1495 37,0.1129,0.1504,0.1451 38,0.1215,0.1349,0.1223 39,0.1092,0.1504,0.1337 40,0.0952,0.1478,0.165 41,0.0833,0.1435,0.1493 42,0.0942,0.1227,0.1667 43,0.1064,0.1528,0.1457 44,0.0846,0.1296,0.1481 45,0.0929,0.1321,0.155 46,0.0873,0.129,0.1487 47,0.0855,0.1316,0.1579 48,0.0924,0.1307,0.1697 49,0.1019,0.1453,0.1571 50,0.1043,0.1029,0.1542 51,0.0865,0.1065,0.1532 52,0.0841,0.1078,0.1505 53,0.09,0.0955,0.1457 54,0.0833,0.1074,0.1414 55,0.0918,0.1308,0.1429 56,0.0594,0.1111,0.1563 57,0.08,0.12,0.1604 58,0.0857,0.1091,0.1344 59,0.0769,0.0991,0.1436 60,0.0935,0.1132,0.1404 61,0.0707,0.101,0.1337 62,0.0918,0.098,0.1282 63,0.0762,0.0968,0.1506 64,0.0947,0.087,0.125 65,0.0891,0.1042,0.1169 66,0.0918,0.119,0.1167 67,0.0761,0.1023,0.1034 68,0.0824,0.1059,0.1092 69,0.0843,0.0952,0.1301 70,0.0988,0.093,0.1204 71,0.0946,0.0964,0.1031 72,0.1111,0.1014,0.1059 73,0.0746,0.1039,0.1059 74,0.0984,0.1039,0.1125 75,0.0938,0.1299,0.1067 76,0.1091,0.0986,0.0933 77,0.0926,0.127,0.0938 78,0.0909,0.1029,0.1129 79,0.1026,0.125,0.0952
Age,White,Black,Hispanic,Asian and other 15,0.001576044,,, 16,0.003016591,0.023730422,0.027358732,0.029398148 17,0.002097902,0.02722881,0.012233149,0.035944472 18,0.010479042,0.023076923,0.038957935,0.014883244 19,0.016640254,0.075739645,0.049818371,0.027427491 20,0.014035088,0.06713615,0.093124246,0.056435644 21,0.031723143,0.100107066,0.086454592,0.035748792 22,0.044299201,0.145659637,0.082930552,0.023148148 23,0.04719764,0.20705347,0.082317831,0.02739726 24,0.045812455,0.282475201,0.145537525,0.041081909 25,0.042887777,0.186239007,0.136509293,0.085660643 26,0.07032967,0.295584416,0.151015801,0.066056064 27,0.068278805,0.315470643,0.140032191,0.045051522 28,0.070200573,0.285328533,0.132834225,0.067830314 29,0.098414795,0.29281768,0.191118489,0.112899897 30,0.062043796,0.372690401,0.172354949,0.111938562 31,0.081464873,0.374146341,0.20546697,0.128923007 32,0.096875,0.337042925,0.190534576,0.067498726 33,0.091926459,0.378824672,0.203125,0.093785568 34,0.067460317,0.364864865,0.181500873,0.100164541 35,0.102222222,0.284880895,0.234911987,0.103749358 36,0.097003155,0.301369863,0.216073479,0.057001795 37,0.107340174,0.352,0.163298872,0.165622389 38,0.096571029,0.316205534,0.191605839,0.111225329 39,0.089214381,0.260781329,0.160633484,0.111315125 40,0.077464789,0.278593914,0.153148966,0.082675337 41,0.091029024,0.245989305,0.163646659,0.111579934 42,0.072924188,0.229982964,0.154011023,0.085651537 43,0.065017668,0.194329592,0.149184149,0.103651685 44,0.057525084,0.200708383,0.129359165,0.065910319 45,0.060569352,0.186402266,0.131380978,0.08221055 46,0.057613169,0.151731721,0.094308405,0.126056879 47,0.055919096,0.157090142,0.098926895,0.060145808 48,0.060058309,0.149939541,0.099927326,0.057617729 49,0.039906103,0.117111995,0.13571665,0.108553655 50,0.04020979,0.123311803,0.124691793,0.058359177
Age,1988,2000,2012 0,0.1258,0.1942,0.2143 1,0.1517,0.1912,0.2301 2,0.1301,0.1799,0.2035 3,0.1448,0.1765,0.2174 4,0.162,0.203,0.2288 5,0.1781,0.1929,0.2333 6,0.1931,0.2361,0.25 7,0.1781,0.2153,0.2479 8,0.2101,0.2069,0.2358 9,0.1825,0.2323,0.2439 10,0.1825,0.2179,0.2422 11,0.1805,0.2381,0.246 12,0.2,0.226,0.2558 13,0.2061,0.2238,0.2462 14,0.2093,0.2297,0.2846 15,0.1985,0.2381,0.2595 16,0.2081,0.2397,0.2759 17,0.2102,0.2288,0.2721
Age,1988,2000,2012 0,0.6341,0.5922,0.6617 1,0.5607,0.6372,0.5752 2,0.5147,0.5811,0.5833 3,0.602,0.5634,0.6636 4,0.5758,0.5909,0.6268 5,0.5234,0.5758,0.5953 6,0.5767,0.5951,0.654 7,0.54,0.6441,0.6283 8,0.6065,0.6383,0.6825 9,0.5632,0.6052,0.6382 10,0.5291,0.5679,0.6111 11,0.5344,0.5975,0.6282 12,0.5652,0.5442,0.6364 13,0.5445,0.5565,0.6571 14,0.5699,0.5929,0.6385 15,0.55,0.6096,0.578 16,0.5829,0.4493,0.5856 17,0.5849,0.5223,0.5822
Age,1988,2000,2012 0,0.3099,0.3271,0.4086 1,0.2776,0.3046,0.4284 2,0.3224,0.316,0.3989 3,0.3065,0.3123,0.3661 4,0.3351,0.2847,0.4144 5,0.3263,0.2864,0.3878 6,0.3468,0.3509,0.3972 7,0.289,0.306,0.3684 8,0.3727,0.2913,0.381 9,0.3396,0.3193,0.3698 10,0.3009,0.3221,0.401 11,0.2612,0.3515,0.3712 12,0.3599,0.3133,0.3984 13,0.3684,0.3642,0.397 14,0.3952,0.3511,0.4059 15,0.3206,0.3448,0.3906 16,0.327,0.3235,0.3993 17,0.2743,0.3244,0.376
Age,1988,2000,2012 0,0.1628,0.2647,0.2353 1,0.18,0.2382,0.282 2,0.2193,0.1938,0.2684 3,0.1527,0.2492,0.2735 4,0.1769,0.3465,0.2707 5,0.1458,0.2397,0.2574 6,0.1349,0.25,0.2521 7,0.1349,0.2705,0.2755 8,0.2343,0.2726,0.3017 9,0.1824,0.2846,0.2511 10,0.1891,0.267,0.2303 11,0.1745,0.3469,0.264 12,0.2651,0.1969,0.1854 13,0.2093,0.2425,0.2664 14,0.2652,0.3153,0.2812 15,0.3395,0.1837,0.2717 16,0.2799,0.3165,0.2812 17,0.3111,0.2346,0.2966