Kursmantel

German to English Bus/Financial Investment / Securities

In a newspaper article about the share performance of a Swiss company, which is described as U-shaped.

Anders verhält es sich mit dem Aufwärtsschwung im U des Kursverlaufs. Er illustriert, wie die Ertragskraft in den vergangenen gut zwei Jahren in den zu grossen Kursmantel hineingewachsen ist.

I have translated Kursverlauf as 'share performance' but I can't find any other instances of the term 'Kursmantel' online and can't gauge its meaning from the context.

I think it might be saying that over the last two years, the profitability has become too much of a coverall for poor performance in other areas, but that's a very tentative interpretation so I would be grateful for any help!