Sampling stages and selection process

168 ANNEX IV SAMPLE DESIGN AND IMPLEMENTATION Because the unweighed sample allocation was not uniform across seasons, uncorrected annual estimates would place relatively larger weights on those seasons which had a large sample spring and summer, thereby distorting the representativeness of national results. Because the sample was stratiied by season, and imposing the assumption that the level of seasonal, international migration is negligible, the weighted distribution can be smoothed out to ensure that the estimated population size by quarter is the same. That is to say, the sample-based estimate of the population of Afghanistan is the same in the summer as it is in the winter. This adjustment is implemented as: Whsq = [probPSU probUSU] [0.25 POPs, 2012 ] ∑hsq HHSIZEhsq where POP is the CSO estimate for the settled population for January 2012 25,500,100. This population is divided by four to uniformly allocate the population to each quarter of the year assuming away seasonal international migration. The denominator term HHSIZEhsq is the size of household h in stratum s sampled in quarter q. The denominator gives the total number of sampled, settled individuals in each stratum by quarter. The adjustment term in the numerator gives the population of individuals for each stratum by quarter as estimated by CSO of the settled population. In order to obtain an expansion factor for the count of individuals the following calculation was made: whsq = Whsq HHSIZEhsq Whsq and whsq are included in the NRVA 2011-12 dataset as sampling weights to produce survey results for the total populations of households and individuals. 169 ANNEX V POPULATION BY AGE AND SEX ANNEX V POPULATION BY AGE AND SEX Table V.1.a: Population, by residence, sex, and by ive-year age groups in thousands Age Urban Rural Kuchi Total Male Female Both sexes Male Female Both sexes Male Female Both sexes Male Female Both sexes 0-4 452 419 871 1,779 1,708 3,486 166 135 301 2,396 2,262 4,658 5-9 459 418 877 1,844 1,670 3,514 138 140 278 2,442 2,228 4,670 10-14 425 402 826 1,425 1,275 2,700 112 83 194 1,962 1,759 3,721 15-19 400 428 828 971 976 1,947 65 57 121 1,436 1,461 2,897 20-24 333 282 616 727 769 1,496 45 53 98 1,105 1,105 2,209 25-29 233 220 453 651 714 1,365 54 61 115 939 995 1,933 30-34 161 161 322 534 521 1,055 38 36 74 733 718 1,451 35-39 141 153 294 452 448 900 34 37 71 628 638 1,265 40-44 120 111 232 356 344 700 25 23 49 501 479 981 45-49 92 89 181 283 254 536 22 18 40 396 361 757 50-54 83 110 193 257 303 559 20 21 41 359 434 793 55-59 60 68 128 198 153 351 13 9 22 271 230 502 60-64 54 53 107 188 142 330 11 9 20 252 205 457 65-69 49 30 79 102 64 166 6 6 12 157 100 257 70-74 40 24 64 92 48 140 7 4 11 140 75 215 75-79 14 10 24 37 15 52 2 3 5 53 28 81 80-84 14 6 20 32 13 45 4 - 4 50 19 69 85+ 11 ... 15 18 5 23 2 - 2 31 9 40 Total 3,141 2,989 6,130 9,945 9,420 19,365 764 696 1,459 13,850 13,105 26,955 Table V.1.b: Population, by residence, sex, and by ive-year age groups in percentages Age Urban Rural Kuchi Total Male Female Both sexes Male Female Both sexes Male Female Both sexes Male Female Both sexes 0-4 14.4 14.0 14.2 17.9 18.1 18.0 21.7 19.5 20.6 17.3 17.3 17.3 5-9 14.6 14.0 14.3 18.5 17.7 18.1 18.1 20.1 19.1 17.6 17.0 17.3 10-14 13.5 13.4 13.5 14.3 13.5 13.9 14.6 11.9 13.3 14.2 13.4 13.8 15-19 12.7 14.3 13.5 9.8 10.4 10.1 8.5 8.2 8.3 10.4 11.1 10.7 20-24 10.6 9.4 10.0 7.3 8.2 7.7 5.9 7.6 6.7 8.0 8.4 8.2 25-29 7.4 7.3 7.4 6.5 7.6 7.0 7.1 8.8 7.9 6.8 7.6 7.2 30-34 5.1 5.4 5.3 5.4 5.5 5.4 4.9 5.2 5.1 5.3 5.5 5.4 35-39 4.5 5.1 4.8 4.5 4.8 4.6 4.5 5.3 4.9 4.5 4.9 4.7 40-44 3.8 3.7 3.8 3.6 3.7 3.6 3.3 3.4 3.3 3.6 3.7 3.6 45-49 2.9 3.0 3.0 2.8 2.7 2.8 2.9 2.6 2.7 2.9 2.8 2.8 50-54 2.6 3.7 3.2 2.6 3.2 2.9 2.6 3.0 2.8 2.6 3.3 2.9 55-59 1.9 2.3 2.1 2.0 1.6 1.8 1.7 1.3 1.5 2.0 1.8 1.9 60-64 1.7 1.8 1.7 1.9 1.5 1.7 1.4 1.4 1.4 1.8 1.6 1.7 65-69 1.6 1.0 1.3 1.0 0.7 0.9 0.7 0.9 0.8 1.1 0.8 1.0 70-74 1.3 0.8 1.0 0.9 0.5 0.7 1.0 0.5 0.8 1.0 0.6 0.8 75-79 0.4 0.3 0.4 0.4 0.2 0.3 0.3 0.4 0.3 0.4 0.2 0.3 80-84 0.4 0.2 0.3 0.3 0.1 0.2 0.5 - 0.3 0.4 0.1 0.3 85+ 0.3 0.1 0.2 0.2 0.1 0.1 0.3 - 0.1 0.2 0.1 0.1 Total 100.0 100.0 100.0 100.0 100.0 100.0 100.0 100.0 100.0 100.0 100.0 100.0