Twenty per cent off sounds appealing to shoppers. Not to investors. On Tuesday, the JC Penney department store chain reported that same-store sales had dropped by nearly a fifth from the year before. It is hard to recall another like-for-like decline of this magnitude, at any company. Even at Gap, an industry problem child, same-store sales bottomed at -14 per cent in the recessionary 2008. Penney shares tanked yesterday.

The issue has little to do with the environment for mid- or low-priced retailers in the US, though. Same-store sales at Macy’s and Kohl’s, also mid-tier department stores, were slightly positive and flat, respectively, in the first quarter. Off-price clothier TJX reported like-for- like sales up 8 per cent.

The issue is the strategic changes instituted by new boss Ron Johnson, who previously ran Apple’s retail operations. His decision to abolish sales commissions has attracted attention, but, like his cost-cutting initiatives and planned store revamps, was instituted too recently to explain the drop off. The culprit seems to be the move from constantly changing promotions to a few stable price tiers. Shoppers appear to have liked the old disorder.