Where it comes from
The line in the source
※パッケージ併売ダウンロードソフト、ダウンロード専用ソフト、追加コンテンツ、 Nintendo Switch Online等の売上高 In English
Digital sales = (1) downloads of titles also sold packaged, (2) download-only software, (3) additional content, (4) NSO. Yen categories, not unit counts.