Change in Accounting Estimate for Self-Insured Claims (Tables)

9 Months Ended

Sep. 30, 2017

Effect of Increase in Cost of Insurance and Claims

The following table summarizes the effect of the increase (decrease) in the cost of insurance claims resulting from unfavorable (favorable) development of prior year self-insured claims estimates on operating income, net income attributable to Landstar System, Inc. and subsidiary and earnings per share attributable to Landstar System, Inc. and subsidiary amounts in the consolidated statements of income for the thirty-nine-week and thirteen-week periods ended September 30, 2017 and September 24, 2016 (in thousands, except per share amounts):

	Thirty Nine Weeks Ended				Thirteen Weeks Ended
	September 30, 2017		September 24, 2016		September 30, 2017		September 24, 2016
Operating income	$	1,327	$	698	$	1,124	$	(2,118	)
Net income attributable to Landstar System, Inc. and subsidiary		825		431		699		(1,309	)
Earnings per share attributable to Landstar System, Inc. and subsidiary	$	0.02	$	0.01	$	0.02	$	(0.03	)
Diluted earnings per share attributable to Landstar System, Inc. and subsidiary	$	0.02	$	0.01	$	0.02	$	(0.03	)