interest expense related to capital lease obligations was $ 1.7 million during both the years ended december 31 , 2013 and 2012 , and $ 1.5 million during the year ended december 31 , 2011 .purchase commitments in the table below , we set forth our enforceable and legally binding purchase obligations as of december 31 , 2013 .some of the amounts included in the table are based on management 2019s estimates and assumptions about these obligations , including their duration , the possibility of renewal , anticipated actions by third parties , and other factors .because these estimates and assumptions are necessarily subjective , our actual payments may vary from those reflected in the table .purchase orders made in the ordinary course of business are excluded from the table below .any amounts for which we are liable under purchase orders are reflected on the consolidated balance sheets as accounts payable and accrued liabilities .these obligations relate to various purchase agreements for items such as minimum amounts of fiber and energy purchases over periods ranging from one to 15 years .total purchase commitments are as follows ( dollars in thousands ) : .
[['2014', '$ 120971'], ['2015', '54757'], ['2016', '14840'], ['2017', '3017'], ['2018', '2545'], ['thereafter', '11536'], ['total', '$ 207666']]
the company purchased a total of $ 61.7 million , $ 27.7 million , and $ 28.5 million during the years ended december 31 , 2013 , 2012 , and 2011 , respectively , under these purchase agreements .the increase in purchase commitments in 2014 , compared with 2013 , relates to the acquisition of boise in fourth quarter 2013 .environmental liabilities the potential costs for various environmental matters are uncertain due to such factors as the unknown magnitude of possible cleanup costs , the complexity and evolving nature of governmental laws and regulations and their interpretations , and the timing , varying costs and effectiveness of alternative cleanup technologies .from 1994 through 2013 , remediation costs at the company 2019s mills and corrugated plants totaled approximately $ 3.2 million .at december 31 , 2013 , the company had $ 34.1 million of environmental-related reserves recorded on its consolidated balance sheet .of the $ 34.1 million , approximately $ 26.5 million related to environmental- related asset retirement obligations discussed in note 14 , asset retirement obligations , and $ 7.6 million related to our estimate of other environmental contingencies .the company recorded $ 7.8 million in 201caccrued liabilities 201d and $ 26.3 million in 201cother long-term liabilities 201d on the consolidated balance sheet .liabilities recorded for environmental contingencies are estimates of the probable costs based upon available information and assumptions .because of these uncertainties , pca 2019s estimates may change .as of the date of this filing , the company believes that it is not reasonably possible that future environmental expenditures for remediation costs and asset retirement obligations above the $ 34.1 million accrued as of december 31 , 2013 , will have a material impact on its financial condition , results of operations , or cash flows .guarantees and indemnifications we provide guarantees , indemnifications , and other assurances to third parties in the normal course of our business .these include tort indemnifications , environmental assurances , and representations and warranties in commercial agreements .at december 31 , 2013 , we are not aware of any material liabilities arising from any guarantee , indemnification , or financial assurance we have provided .if we determined such a liability was probable and subject to reasonable determination , we would accrue for it at that time. .

Question: what percentage of total purchase commitments are due after 2018?
Answer: 6%