
	Payments Due By Period
(in thousands)	2016		2017		2018		2019		2020		Thereafter		Total
Purchase obligations (1)	$	19,364	$	10,035	$	6,669	$	5,829	$	5,031	$	23,581	$	70,509
Operating leases (2)
Lease obligations		11,467		10,146		8,819		7,122		5,219		24,735		67,508
Sublease income		(3,336)		(2,342)		(1,441)		(1,028)		(611)		(1,748)		(10,506)
Net lease obligation		8,131		7,804		7,378		6,094		4,608		22,987		57,002
Workers’ compensation obligations (3)		3,599		2,425		1,822		1,356		1,045		6,361		16,608
Total (4)	$	31,094	$	20,264	$	15,869	$	13,279	$	10,684	$	52,929	$	144,119

(1)

Represents our purchase obligations primarily related to printing outsource agreements and capital expenditures for property, plant and equipment expiring at various dates through 2028.

(2)

Represents minimum rental commitments under operating leases with non‑cancelable terms in excess of one year and sublease income from leased space. We rent certain facilities and equipment under operating leases expiring at various dates through 2028. Total rental expense, included in other operating expenses, from continuing operations amounted to $11.6 million, $12.5 million and $11.2 million in 2015, 2014 and 2013, respectively. Most of the leases provide that we pay taxes, maintenance, insurance and certain other operating expenses applicable to the leased premises in addition to the minimum monthly payments. Some of the operating leases have built in escalation clauses. We sublease office space to other companies under noncancellable agreements that expire at various dates through 2024. Sublease income from operating leases totaled $4.6 million, $2.2 million and $3.9 million in 2015, 2014 and 2013, respectively.

(3)

Represents the expected insurance payments of undiscounted ultimate losses, net of estimated insurance recoveries of approximately $3.2 million, and was based on our historical payment patterns. We retain the risk for workers’ compensation resulting from uninsured deductibles per accident or occurrence that are subject to annual aggregate limits. Losses up to the deductible amounts are accrued based upon known claims incurred and an estimate of claims incurred but not reported. For the year ended December 27, 2015, we compiled our historical data pertaining to the self‑insurance experiences and actuarially developed the ultimate loss associated with our self‑insurance programs for workers’ compensation liability. We believe that the actuarial valuation provides the best estimate of the ultimate losses to be expected under these programs. The undiscounted ultimate losses of all our self‑insurance reserves related to our workers’ compensation liabilities, net of insurance recoveries at December 27, 2015, and December 28, 2014, were $16.6 million and $18.0 million, respectively. We discount the net amount above to present value using an approximate risk‑free rate over the average life of our insurance claims. For the years ended December 27, 2015, and December 28, 2014, the discount rate used was 1.8% and 2.0%, respectively. The present value of all self‑insurance reserves, net of estimated insurance recoveries, for our workers’ compensation liability recorded at December 27, 2015, and December 28, 2014, was $15.3 million and $17.5 million, respectively.