Frequencies for first 10,000 rows of vin_bt variable in vehicle dataset : vin_bt | Freq. Percent Cum. ------------+----------------------------------- | 247 2.47 2.47 2D | 303 3.03 5.50 2F | 2 0.02 5.52 2H | 622 6.22 11.74 2L | 50 0.50 12.24 2P | 11 0.11 12.35 2T | 99 0.99 13.34 2W | 14 0.14 13.48 3D | 13 0.13 13.61 4D | 2,371 23.71 37.32 4H | 139 1.39 38.71 4L | 7 0.07 38.78 4P | 16 0.16 38.94 4T | 11 0.11 39.05 4W | 85 0.85 39.90 8V | 1 0.01 39.91 99 | 513 5.13 45.04 AT | 12 0.12 45.16 BU | 3 0.03 45.19 CB | 91 0.91 46.10 CC | 61 0.61 46.71 CG | 15 0.15 46.86 CL | 2 0.02 46.88 CP | 936 9.36 56.24 CV | 83 0.83 57.07 CW | 30 0.30 57.37 CY | 8 0.08 57.45 DP | 2 0.02 57.47 DS | 366 3.66 61.13 EC | 9 0.09 61.22 EN | 2 0.02 61.24 ES | 6 0.06 61.30 EV | 3 0.03 61.33 EW | 1 0.01 61.34 FB | 2 0.02 61.36 FC | 2 0.02 61.38 GL | 4 0.04 61.42 HB | 2 0.02 61.44 HT | 2 0.02 61.46 IC | 65 0.65 62.11 IE | 10 0.10 62.21 LB | 7 0.07 62.28 LL | 3 0.03 62.31 MH | 7 0.07 62.38 MP | 1 0.01 62.39 MS | 3 0.03 62.42 MX | 6 0.06 62.48 MY | 17 0.17 62.65 NB | 11 0.11 62.76 PC | 278 2.78 65.54 PK | 1,470 14.70 80.24 PS | 133 1.33 81.57 RD | 2 0.02 81.59 RS | 350 3.50 85.09 RT | 9 0.09 85.18 S2 | 31 0.31 85.49 SD | 19 0.19 85.68 SN | 2 0.02 85.70 SV | 349 3.49 89.19 SW | 272 2.72 91.91 T | 2 0.02 91.93 TB | 38 0.38 92.31 TL | 46 0.46 92.77 TM | 89 0.89 93.66 UT | 504 5.04 98.70 VN | 126 1.26 99.96 VW | 1 0.01 99.97 XT | 1 0.01 99.98 YY | 2 0.02 100.00 ------------+----------------------------------- Total | 10,000 100.00 by Jean Roth , jroth@nber.org , 18 Apr 2016