Here Oricon Manga sales from November 18, 2019 to May 17, 2020.
Top 10 Best Selling Manga Series First Half 2020
https://www.oricon.co.jp/special/54719/5/
1 - Kimetsu no Yaiba (45,297,633 copies).
2 - One Piece (4,885,538 copies).
3 - Go-Tōbun no Hanayome (4,240,192 copies).
4 - Kingdom (3,512,571 copies).
5 - Boku no Hero Academia (3,339,656 copies).
6 - The Promised Neverland (3,102,313 copies).
7 - Haikyû!! (2,996,317 copies).
8 - Shingeki no Kyojin (2,212,135 copies).
9 - Jibaku Shounen Hanako-kun (2,138,410 copies).
10 - Spy x Family (1,796,759 copies).
Top 10 Best Selling Manga Volumes First Half 2020
https://www.oricon.co.jp/special/54719/4/
1 - Kimetsu no Yaiba 18 (3,035,555 copies).
3 - Kimetsu no Yaiba 19 (2,829,174 copies).
3 - Kimetsu no Yaiba 01 (2,267,744 copies).
4 - Kimetsu no Yaiba 12 (2,237,092 copies).
5 - Kimetsu no Yaiba 11 (2,234,515 copies).
6 - Kimetsu no Yaiba 14 (2,233,412 copies).
7 - Kimetsu no Yaiba 13 (2,223,961 copies).
8 - Kimetsu no Yaiba 07 (2,223,867 copies).
9 - Kimetsu no Yaiba 08 (2,218,826 copies).
10 - Kimetsu no Yaiba 09 (2,216,999 copies).
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20 - One Piece 95 (1,955,897 copies).
21 - One Piece 96 (1,688,363 copies).