Where it comes from
The line in the source
発売から3カ月で出荷本数500万本突破 ... シリーズ最高の大ヒットを記録しており In English
Shipments passed 5m units three months after release; recorded as the series' biggest hit.
Explore / Figure
Record
Diamond pearl shipments 3months, Sep 28–Dec 2006
5 millions of units Sep 28–Dec 2006
ReportedReported by a reliable secondary source, or read carefully from filed documents.
Found in one pass only. The research team reads every source twice, independently; this record turned up in one reading but not the other, so treat it as less certain than its grade.