Shares in American Airlines' parent company fell 85 percent Tuesday after the firm filed for Chapter 11 bankruptcy. Minutes after trade AMR resumed late on Tuesday the stock was trading down 84.57 percent from Monday's close, at around 25 cents a piece. American Airlines' parent company AMR filed for Chapter 11 bankruptcy Tuesday, as the troubled firm moved to put its finances in order while keeping planes in the sky and passengers in seats. "Chapter 11 reorganization is in the best interest of the company and its stakeholders," the firm said in an early-morning statement, which also announced the departure of chairman and chief executive Gerard Arpey. Rumors had swirled for months that AMR would file for bankruptcy protection, after an unusual spike in pilot retirements, with the pilots trying to sell off their own stocks in the company. Before Tuesday's selloff shares in AMR had plunged 35 percent since the beginning of November, leaving the stock at $1.62 before US markets opened Tuesday.