Spirit’s shares sank as much as 42% in premarket trading Friday and its so-called “loyalty bonds,” about $1 billion of 8% notes due 2025, declined as much as 6 cents on the dollar to 45 cents, according to pricing source Trace.

The stock crashed 34% to $1.39 in premarket trading, putting it on course to open at a record low. Even before Friday’s plunge, Spirit shares were down 86% for the year with inv