Frequencies for first 10,000 rows of vin_bt variable in vehicle dataset : vin_bt | Freq. Percent Cum. ------------+----------------------------------- | 56 0.56 0.56 2D | 243 2.43 2.99 2H | 451 4.51 7.50 2L | 47 0.47 7.97 2P | 36 0.36 8.33 2T | 47 0.47 8.80 2W | 37 0.37 9.17 3C | 81 0.81 9.98 3D | 3 0.03 10.01 3P | 2 0.02 10.03 4B | 1 0.01 10.04 4C | 97 0.97 11.01 4D | 2,563 25.63 36.64 4H | 67 0.67 37.31 4L | 4 0.04 37.35 4P | 28 0.28 37.63 4T | 3 0.03 37.66 4W | 154 1.54 39.20 99 | 557 5.57 44.77 AT | 19 0.19 44.96 BU | 12 0.12 45.08 CB | 83 0.83 45.91 CC | 94 0.94 46.85 CG | 32 0.32 47.17 CH | 1 0.01 47.18 CL | 1 0.01 47.19 CP | 715 7.15 54.34 CV | 98 0.98 55.32 CW | 58 0.58 55.90 DP | 1 0.01 55.91 DS | 444 4.44 60.35 EC | 16 0.16 60.51 EN | 3 0.03 60.54 ES | 9 0.09 60.63 EV | 2 0.02 60.65 EW | 2 0.02 60.67 FB | 3 0.03 60.70 FC | 7 0.07 60.77 GL | 5 0.05 60.82 HT | 1 0.01 60.83 IC | 53 0.53 61.36 IE | 8 0.08 61.44 LB | 2 0.02 61.46 LL | 6 0.06 61.52 MH | 5 0.05 61.57 MK | 1 0.01 61.58 MP | 3 0.03 61.61 MS | 4 0.04 61.65 MX | 8 0.08 61.73 MY | 18 0.18 61.91 NB | 3 0.03 61.94 PC | 364 3.64 65.58 PK | 1,124 11.24 76.82 PN | 1 0.01 76.83 PS | 130 1.30 78.13 RD | 4 0.04 78.17 RS | 473 4.73 82.90 RT | 9 0.09 82.99 S1 | 1 0.01 83.00 S2 | 20 0.20 83.20 SD | 1 0.01 83.21 SN | 5 0.05 83.26 SV | 429 4.29 87.55 SW | 254 2.54 90.09 T | 4 0.04 90.13 TB | 33 0.33 90.46 TL | 36 0.36 90.82 TM | 106 1.06 91.88 UT | 720 7.20 99.08 VN | 71 0.71 99.79 VW | 1 0.01 99.80 WW | 4 0.04 99.84 YY | 16 0.16 100.00 ------------+----------------------------------- Total | 10,000 100.00 by Jean Roth , jroth@nber.org , 18 Apr 2016