All boards

+------+-----------------------------+------------+----------------------------------+
| Rank |           Artist            | 2018 Sales |             # Albums             |
+------+-----------------------------+------------+----------------------------------+
|    7 | TWICE                       |    418,719 | 3 + 1 repackage + 1 older        |
|   15 | Red Velvet                  |    207,755 | 3 (2 ver. for 1)                 |
|   21 | BLACKPINK                   |    145,361 | 1                                |
|   22 | IZ*ONE                      |    140,011 | 1 + Kihno ver.                   |
|   27 | MAMAMOO                     |    105,104 | 3                                |
|   28 | Gfriend                     |     84,856 | 2 (2 ver. for 1)                 |
|   33 | Lovelyz                     |     62,934 | 2                                |
|   38 | WJSN                        |     55,786 | 1                                |
|   39 | fromis_9                    |     54,487 | 3 (2 ver. for 2)                 |
|   41 | Oh My Girl                  |     50,961 | 2                                |
|   42 | Taeyeon (Girls' Generation) |     49,541 | 1                                |
|   46 | Apink                       |     44,522 | 2                                |
|   56 | Girls' Generation-Oh!GG     |     31,738 | 1                                |
|   57 | Weki Meki                   |     30,803 | 2 (3 ver. on 1, 2 ver. on other) |
|   61 | LOONA                       |     25,002 | 1 (4 ver.)                       |
|   65 | gugudan                     |     20,836 | 2                                |
|   67 | MOMOLAND                    |     19,310 | 2                                |
|   68 | UNI.T                       |     18,415 | 2                                |
|   71 | Dreamcatcher                |     16,558 | 1 (2 ver.)                       |
|   72 | LOONAyyxy                   |     15,962 | 1 (3 ver.)                       |
|   74 | AOA                         |     15,744 | 1                                |
|   75 | (G)I-DLE                    |     15,155 | 1                                |
|   78 | Pristin V                   |     13,814 | 1                                |
|   79 | Kim Chungha                 |     13,293 | 2                                |
|   81 | Yuri (Girls' Generation)    |     12,882 | 1                                |
|   83 | Jeong Eunji (Apink)         |     11,731 | 1                                |
|   85 | Oh My Girl Banhana          |     11,590 | 1                                |
|   90 | gugudan-SEMINA              |      8,787 | 1                                |
|   93 | DIA                         |      7,789 | 1                                |
|   96 | GWSN                        |      6,507 | 1                                |
|   97 | Suzy                        |      6,289 | 1                                |
|   98 | EXID                        |      6,272 | 1                                |
|  101 | APRIL                       |      5,506 | 1                                |
|  103 | Sunmi                       |      5,231 | 1                                |
|  104 | BoA                         |      5,154 | 1                                |
|  105 | ELRIS                       |      4,812 | 1                                |
|  108 | CLC                         |      4,384 | 1                                |
+------+-----------------------------+------------+----------------------------------+