Knight-Swift Transportation Holdings Inc. KNX, +1.08% said late Thursday that it was lowering its fourth-quarter guidance because the trucking industry has too much capacity for shipping for the demand during the holiday quarter. Knight-Swift stock fell more than 3.6% in the extended session. The company said that it believes there is too much capacity because there are fewer replacement orders for long-haul trucks, trucking employment has contracted and there are "trucking business failures." As a result, the company is expecting adjusted fourth-quarter earnings of 50 cents to 52 cents a share versus its previous expectation of 62 cents to 65 cents a share. Knight-Swift adjusts earnings for tax impacts and noncash impairments, among other items. Knight-Swift shares have gained 43% this year, as the S&P 500 index SPX, +1.59% gained 28%.