NEW YORK (AP) — Chunky bootmaker Dr. Martens is warning of a tough year ahead.

Dr. Martens shares plunged more than 30% Tuesday after the iconic British brand forecast wholesale revenue in the U.S., its largest market, would decline by double-digits compared with last year.

Trading in Dr. Martens stock was temporarily halted on the London Stock Exchange early Tuesday as it sank to a record-low 0.64 pounds, according to FactSet.

That could translate into a sizeable hit to profits, with the company pointing to a base projected impact of 20 million pounds ($24.9 million) on pretax earnings year-over-year. In-season orders from wholesale customers could help ease U.S. revenue expectations, the company noted, but those are difficult to predict.