Frequencies for first 10,000 rows of vin_bt variable in vehicle dataset : vin_bt | Freq. Percent Cum. ------------+----------------------------------- | 11 0.11 0.11 2D | 90 0.90 1.01 2H | 280 2.80 3.81 2L | 23 0.23 4.04 2P | 18 0.18 4.22 2T | 9 0.09 4.31 2W | 30 0.30 4.61 3C | 65 0.65 5.26 3P | 20 0.20 5.46 4B | 4 0.04 5.50 4C | 315 3.15 8.65 4D | 2,631 26.31 34.96 4H | 78 0.78 35.74 4L | 2 0.02 35.76 4P | 27 0.27 36.03 4T | 1 0.01 36.04 4W | 241 2.41 38.45 5D | 2 0.02 38.47 99 | 568 5.68 44.15 AT | 42 0.42 44.57 BU | 11 0.11 44.68 C4 | 4 0.04 44.72 CB | 51 0.51 45.23 CC | 66 0.66 45.89 CG | 29 0.29 46.18 CH | 1 0.01 46.19 CP | 576 5.76 51.95 CV | 99 0.99 52.94 CW | 365 3.65 56.59 DP | 1 0.01 56.60 DS | 493 4.93 61.53 EC | 14 0.14 61.67 EN | 2 0.02 61.69 ES | 12 0.12 61.81 EV | 1 0.01 61.82 EW | 1 0.01 61.83 FB | 4 0.04 61.87 FC | 4 0.04 61.91 GG | 1 0.01 61.92 GL | 3 0.03 61.95 HT | 2 0.02 61.97 IC | 36 0.36 62.33 IE | 10 0.10 62.43 LB | 16 0.16 62.59 LL | 2 0.02 62.61 MH | 1 0.01 62.62 MP | 1 0.01 62.63 MS | 6 0.06 62.69 MX | 8 0.08 62.77 MY | 9 0.09 62.86 PC | 349 3.49 66.35 PK | 682 6.82 73.17 PS | 92 0.92 74.09 RD | 13 0.13 74.22 RS | 753 7.53 81.75 RT | 14 0.14 81.89 SN | 2 0.02 81.91 SV | 370 3.70 85.61 SW | 82 0.82 86.43 T | 4 0.04 86.47 TB | 27 0.27 86.74 TL | 19 0.19 86.93 TM | 64 0.64 87.57 UT | 1,205 12.05 99.62 VN | 15 0.15 99.77 YY | 23 0.23 100.00 ------------+----------------------------------- Total | 10,000 100.00 by Jean Roth , jroth@nber.org , 18 Apr 2016