rose 9.5% last week after predicting its second-quarter earnings would come in at the high end of analysts' views. The country's No. 4 trucking company told investors at a conference that a pickup in economic activity was helping its bottom line and would propel earnings to the high end of a $1.28 to $1.41 a share range. Chief Executive Jeff Crowe said the company was also benefiting from a drop in shipments by its competitors. Crowe said shipments rose in building materials, chemicals and all other segments in which Landstar operates, except for automotive vehicles.