|  Callsign structure | # | Callsign structure, C - char, D - digit | Example | Callsigns | % | QSOs | % | 
|---|
 | 1 | C D C C  | K0AD | 377 | 36.71 % |  | 627 | 38.16 % |  |  | 2 | C D C C C  | F6AGM | 195 | 18.99 % |  | 288 | 17.53 % |  |  | 3 | C C D C  | AA0O | 191 | 18.60 % |  | 335 | 20.39 % |  |  | 4 | C C D C C  | AA0AI | 143 | 13.92 % |  | 234 | 14.24 % |  |  | 5 | C C D C C C  | KA1IOR | 115 | 11.20 % |  | 152 | 9.25 % |  |  | 6 | C D D C C  | V31XX | 2 | 0.19 % |  | 3 | 0.18 % |  |  | 7 | C C D C / D  | KL2A/5 | 2 | 0.19 % |  | 2 | 0.12 % |  |  | 8 | C C C D C  | KCR9K | 1 | 0.10 % |  | 1 | 0.06 % |  |  | 9 | C D C C / D  | K2ZR/4 | 1 | 0.10 % |  | 1 | 0.06 % |  |  
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