In my panel data, There are 20 individuals and 32-time points. Within the data set, the "Exchange rate " is one of the variables. This variable is the same for all individuals, but the variation is only along with the id, not across the ids. For example, ID=7 has different values across the time and Id-8 also replaces the same value of Id-7. I want to find out the standard deviation of exchange rate. When I use the code " bysort id qdate: egen SD=sd(ex_rate) " , it gives only missing value. How can I the standard deviation of each time point?

Thanks for your comments and support.


input float(id qdate) double(employment gross_salary) float indp double(exp_index imp_index indpturnover) float(export_intensity import_intensity openness) double ex_rate str154 industry
7 200 101.47601095104292 93.1076213318248 96.11465 93 78.6 90.8 .9675944 .8177733 1.7853677 98.25576490087526 "B07. (Mining Of Metal Ores)"
7 201 82.9028259163672 78.59734268270924 105.02743 100.7 85.7 102.93333333333334 .9587972 .8159773 1.7747746 100.52078926423046 "B07. (Mining Of Metal Ores)"
7 202 108.11807712238392 101.57195054380887 99.6081 97.4 116.8 99.63333333333333 .9778321 1.1725954 2.1504276 101.8434312282335 "B07. (Mining Of Metal Ores)"
7 203 107.50307099540791 126.72310020227583 99.2498 108.9 119 106.7 1.0972314 1.198995 2.2962263 99.38001057027785 "B07. (Mining Of Metal Ores)"
7 204 128.2902780871973 136.63845727917146 97.72701 114.5 130.3 110.03333333333335 1.171631 1.333306 2.504937 92.32040908741166 "B07. (Mining Of Metal Ores)"
7 205 125.21524745231721 147.0374903110376 104.8035 123 139.4 113.40000000000002 1.173625 1.3301084 2.5037334 90.23724799410688 "B07. (Mining Of Metal Ores)"
7 206 103.8130342335518 107.37606200345509 127.37654 130.1 166.7 165.6 1.0213811 1.3087182 2.3300993 82.57419111516431 "B07. (Mining Of Metal Ores)"
7 207 119.31118863334744 124.5465584049085 133.28853 127.6 184.5 178.79999999999998 .9573217 1.384215 2.3415368 85.60800112009628 "B07. (Mining Of Metal Ores)"
7 208 126.32225848087405 172.6723159244751 113.53712 121.8 155.2 177.9 1.0727769 1.366954 2.439731 89.52632793845525 "B07. (Mining Of Metal Ores)"
7 209 134.19433690616708 159.6130651402711 132.3032 119.7 145.4 163.20000000000002 .90474 1.0989908 2.0037308 91.02256666023368 "B07. (Mining Of Metal Ores)"
7 210 137.6383712172328 178.71826536160657 134.00514 120.3 143.7 169.03333333333333 .8977267 1.0723469 1.9700737 90.71670570605798 "B07. (Mining Of Metal Ores)"
7 211 120.29519843650907 144.37727255869976 132.3032 116.9 116.3 187.5 .8835765 .8790414 1.762618 91.89055044911068 "B07. (Mining Of Metal Ores)"
7 212 130.25829769352057 195.88876176305996 128.09315 120.86 125.89 177.70000000000002 .943532 .9828004 1.9263325 93.30412404813892 "B07. (Mining Of Metal Ores)"
7 213 128.2902780871973 178.47642738412128 160.47475 122.72 137.52 168.13333333333333 .7647309 .8569573 1.621688 89.36099769295487 "B07. (Mining Of Metal Ores)"
7 214 127.42926950943087 216.68682782679224 167.5512 130.79 141.68 181.96666666666667 .7805972 .8455922 1.6261894 85.03761177311996 "B07. (Mining Of Metal Ores)"
7 215 115.74415309688654 164.20798671249102 167.05856 135.07 150.32 191.4333333333333 .8085189 .8998042 1.708323 83.5661725881666 "B07. (Mining Of Metal Ores)"
7 216 130.62730136970617 208.70617456977868 142.6492 146.85 168.23 193.03333333333333 1.0294485 1.1793267 2.208775 80.54062909550966 "B07. (Mining Of Metal Ores)"
7 217 127.67527196022128 225.63483299374684 146.05307 135.61 147.25 167.9333333333333 .9284981 1.0081952 1.9366933 86.48425142124829 "B07. (Mining Of Metal Ores)"
7 218 130.62730136970617 219.58888355661537 152.63687 143.26 130.9 174.29999999999998 .9385675 .857591 1.7961584 85.64933368147136 "B07. (Mining Of Metal Ores)"
7 219 125.58425112850281 192.01935412329584 149.27779 144.12 126.17 187.0333333333333 .9654484 .8452028 1.8106512 87.50929894335063 "B07. (Mining Of Metal Ores)"
7 220 119.31118863334744 232.4062963633341 121.55413 139.31 127.82 149.53333333333333 1.1460738 1.051548 2.1976218 86.5834495685485 "B07. (Mining Of Metal Ores)"
7 221 127.06026583324527 255.38090422443372 135.97581 160.93 114.49 168.76666666666668 1.1835192 .841988 2.0255072 81.99553525591298 "B07. (Mining Of Metal Ores)"
7 222 125.95325480468844 234.82467613818667 142.82835 158.5 109.22 166.9 1.1097237 .7646941 1.8744178 76.01058036879927 "B07. (Mining Of Metal Ores)"
7 223 119.55719108413786 244.74003321508232 137.05072 136.29 106.77 182 .9944494 .7790546 1.773504 81.97073571908793 "B07. (Mining Of Metal Ores)"
7 224 115.62115187149134 274.48610444576923 109.9093 137.22 98.8 154.33333333333334 1.248484 .898923 2.147407 84.83094896624449 "B07. (Mining Of Metal Ores)"
7 225 106.02705629066547 238.93592175543608 125.0028 139.23 103.97 148.36666666666665 1.1138151 .8317414 1.9455565 84.21922705789308 "B07. (Mining Of Metal Ores)"
7 226 102.82902443039016 244.49819523759706 126.03292 154.06 100.78 177.93333333333337 1.222379 .7996324 2.0220113 83.92989912826742 "B07. (Mining Of Metal Ores)"
7 227 109.71709305252158 268.4401550086377 141.75343 204.77 116.96 217.9333333333333 1.4445505 .8250946 2.2696452 77.35802186962735 "B07. (Mining Of Metal Ores)"
7 228 132.34931852523903 330.1088392673788 129.66072 245.9 176.75 219.73333333333335 1.896488 1.363173 3.259661 75.11779704309723 "B07. (Mining Of Metal Ores)"
7 229 117.46617025241939 301.0882819691477 136.0206 221.03 193.08 215.73333333333335 1.6249745 1.419491 3.044465 76.78763252265105 "B07. (Mining Of Metal Ores)"
7 230 127.67527196022128 301.57195792411824 153.75658 211.08 154.48 223.16666666666666 1.3728193 1.004705 2.3775244 75.77911802509874 "B07. (Mining Of Metal Ores)"
7 231 134.07133568077188 348.2466875787733 157.4292 225.75 187.91 227.5 1.433978 1.193616 2.627594 71.36480047023862 "B07. (Mining Of Metal Ores)"
8 200 108.26758147512865 107.8369905956113 62.82127 99.9 96.8 78.96666666666667 1.5902257 1.5408794 3.131105 98.25576490087526 "B08. (Other Mining And Quarrying)"
8 201 84.80274442538592 82.75862068965517 102.38066 99.5 95.7 101.3 .9718632 .9347469 1.90661 100.52078926423046 "B08. (Other Mining And Quarrying)"
8 202 104.97427101200685 110.09404388714734 119.19933 102.5 104.6 111.90000000000002 .8599041 .8775217 1.7374258 101.8434312282335 "B08. (Other Mining And Quarrying)"
8 203 101.95540308747854 99.31034482758622 115.59872 98.1 103 107.83333333333333 .8486254 .8910133 1.7396387 99.38001057027785 "B08. (Other Mining And Quarrying)"
8 204 97.4271012006861 104.32601880877745 91.57882 104.9 123.6 101.59999999999998 1.1454613 1.349657 2.4951184 92.32040908741166 "B08. (Other Mining And Quarrying)"
8 205 120.06861063464837 133.41692789968653 131.32773 112.5 129.6 126.46666666666665 .8566356 .9868441 1.8434796 90.23724799410688 "B08. (Other Mining And Quarrying)"
8 206 117.87307032590051 136.1755485893417 147.67262 122.1 144.7 142.63333333333333 .826829 .9798702 1.806699 82.57419111516431 "B08. (Other Mining And Quarrying)"
8 207 113.61921097770154 120.37617554858934 150.27834 129.1 160.3 141.9 .8590726 1.0666873 1.92576 85.60800112009628 "B08. (Other Mining And Quarrying)"
8 208 133.37907375643223 168.27586206896552 94.75304 129.1 168.7 120.90000000000002 1.3624892 1.7804177 3.142907 89.52632793845525 "B08. (Other Mining And Quarrying)"
8 209 109.63979416809606 126.64576802507838 141.4663 133.6 164.6 146.16666666666666 .9443946 1.1635281 2.1079226 91.02256666023368 "B08. (Other Mining And Quarrying)"
8 210 127.47855917667239 168.27586206896552 152.50504 140.3 157.3 154.16666666666666 .9199696 1.0314413 1.951411 90.71670570605798 "B08. (Other Mining And Quarrying)"
8 211 130.63464837049742 152.2257053291536 158.71135 143.2 153.2 149.83333333333334 .9022669 .9652744 1.8675413 91.89055044911068 "B08. (Other Mining And Quarrying)"
8 212 137.6329331046312 199.62382445141066 101.33837 144.33 160.11 134.06666666666666 1.4242384 1.5799544 3.004193 93.30412404813892 "B08. (Other Mining And Quarrying)"
8 213 144.08233276157804 201.3793103448276 139.47647 151.1 158.27 173.29999999999998 1.0833368 1.1347433 2.2180803 89.36099769295487 "B08. (Other Mining And Quarrying)"
8 214 121.44082332761577 160.25078369905958 152.03127 165.14 159.65 178.29999999999998 1.086224 1.050113 2.1363368 85.03761177311996 "B08. (Other Mining And Quarrying)"
8 215 139.55403087478558 185.3291536050157 136.96553 170.38 158.44 177.0666666666667 1.2439626 1.1567874 2.40075 83.5661725881666 "B08. (Other Mining And Quarrying)"
8 216 136.9468267581475 237.99373040752354 105.46014 184.53 185.21 160.23333333333332 1.7497606 1.7562087 3.505969 80.54062909550966 "B08. (Other Mining And Quarrying)"
8 217 142.84734133790735 221.4420062695925 122.18405 175.07 175.35 171.6 1.4328384 1.43513 2.867968 86.48425142124829 "B08. (Other Mining And Quarrying)"
8 218 129.12521440823326 192.85266457680254 132.1805 181.51 178.75 181.86666666666665 1.373198 1.3523176 2.7255156 85.64933368147136 "B08. (Other Mining And Quarrying)"
8 219 140.51457975986278 238.49529780564265 127.11121 188.99 184.95 178.23333333333335 1.4868083 1.455025 2.941833 87.50929894335063 "B08. (Other Mining And Quarrying)"
8 220 142.84734133790735 268.0877742946709 97.8799 203.14 188.46 166.13333333333335 2.0754006 1.925421 4.0008216 86.5834495685485 "B08. (Other Mining And Quarrying)"
8 221 143.39622641509433 255.0470219435737 141.41891 218.86 208.44 216.19999999999996 1.5476006 1.4739188 3.0215194 81.99553525591298 "B08. (Other Mining And Quarrying)"
8 222 127.2041166380789 219.68652037617557 165.72307 236.82 220.96 217.70000000000002 1.4290105 1.3333087 2.762319 76.01058036879927 "B08. (Other Mining And Quarrying)"
8 223 135.43739279588337 260.0626959247649 163.54375 232.74 224.03 224.1 1.4231055 1.3698475 2.792953 81.97073571908793 "B08. (Other Mining And Quarrying)"
8 224 136.53516295025727 315.98746081504703 107.44995 233.67 218.42 200 2.174687 2.0327604 4.207447 84.83094896624449 "B08. (Other Mining And Quarrying)"
8 225 126.38078902229844 265.57993730407526 148.85703 233.81 214.15 241.6 1.570702 1.4386288 3.0093305 84.21922705789308 "B08. (Other Mining And Quarrying)"
8 226 139.9656946826758 305.7053291536051 143.12448 245.49 203.45 217.0333333333333 1.7152202 1.42149 3.13671 83.92989912826742 "B08. (Other Mining And Quarrying)"
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