consist of first and second liens , the charge-off amounts for the pool are proportionate to the composition of first and second liens in the pool . our experience has been that the ratio of first to second lien loans has been consistent over time and is appropriately represented in our pools used for roll-rate calculations . generally , our variable-rate home equity lines of credit have either a seven or ten year draw period , followed by a 20 year amortization term . during the draw period , we have home equity lines of credit where borrowers pay interest only and home equity lines of credit where borrowers pay principal and interest . based upon outstanding balances at december 31 , 2012 , the following table presents the periods when home equity lines of credit draw periods are scheduled to end . table 39 : home equity lines of credit 2013 draw period end in millions interest product principal interest product .

interestonlyproduct: 2013: 1338
2014: 2048
2015: 2024
2016: 1571
2017: 3075
2018 and thereafter: 5497
total ( a ): 15553
principalandinterestproduct: 2013: 221
2014: 475
2015: 654
2016: 504
2017: 697
2018 and thereafter: 4825
total ( a ): 7376

( a ) includes approximately $ 166 million , $ 208 million , $ 213 million , $ 61 million , $ 70 million and $ 526 million of home equity lines of credit with balloon payments with draw periods scheduled to end in 2013 , 2014 , 2015 , 2016 , 2017 and 2018 and thereafter , respectively . we view home equity lines of credit where borrowers are paying principal and interest under the draw period as less risky than those where the borrowers are paying interest only , as these borrowers have a demonstrated ability to make some level of principal and interest payments . based upon outstanding balances , and excluding purchased impaired loans , at december 31 , 2012 , for home equity lines of credit for which the borrower can no longer draw ( e.g. , draw period has ended or borrowing privileges have been terminated ) , approximately 3.86% ( 3.86 % ) were 30-89 days past due and approximately 5.96% ( 5.96 % ) were greater than or equal to 90 days past due . generally , when a borrower becomes 60 days past due , we terminate borrowing privileges , and those privileges are not subsequently reinstated . at that point , we continue our collection/recovery processes , which may include a loss mitigation loan modification resulting in a loan that is classified as a tdr . see note 5 asset quality in the notes to consolidated financial statements in item 8 of this report for additional information . loan modifications and troubled debt restructurings consumer loan modifications we modify loans under government and pnc-developed programs based upon our commitment to help eligible homeowners and borrowers avoid foreclosure , where appropriate . initially , a borrower is evaluated for a modification under a government program . if a borrower does not qualify under a government program , the borrower is then evaluated under a pnc program . our programs utilize both temporary and permanent modifications and typically reduce the interest rate , extend the term and/or defer principal . temporary and permanent modifications under programs involving a change to loan terms are generally classified as tdrs . further , certain payment plans and trial payment arrangements which do not include a contractual change to loan terms may be classified as tdrs . additional detail on tdrs is discussed below as well as in note 5 asset quality in the notes to consolidated financial statements in item 8 of this report . a temporary modification , with a term between three and 60 months , involves a change in original loan terms for a period of time and reverts to a calculated exit rate for the remaining term of the loan as of a specific date . a permanent modification , with a term greater than 60 months , is a modification in which the terms of the original loan are changed . permanent modifications primarily include the government-created home affordable modification program ( hamp ) or pnc-developed hamp-like modification programs . for consumer loan programs , such as residential mortgages and home equity loans and lines , we will enter into a temporary modification when the borrower has indicated a temporary hardship and a willingness to bring current the delinquent loan balance . examples of this situation often include delinquency due to illness or death in the family , or a loss of employment . permanent modifications are entered into when it is confirmed that the borrower does not possess the income necessary to continue making loan payments at the current amount , but our expectation is that payments at lower amounts can be made . residential mortgage and home equity loans and lines have been modified with changes in terms for up to 60 months , although the majority involve periods of three to 24 months . we also monitor the success rates and delinquency status of our loan modification programs to assess their effectiveness in serving our customers 2019 needs while mitigating credit losses . the following tables provide the number of accounts and unpaid principal balance of modified consumer real estate related loans as well as the number of accounts and unpaid principal balance of modified loans that were 60 days or more past due as of six months , nine months , twelve months and fifteen months after the modification date . the pnc financial services group , inc . 2013 form 10-k 91 .

Questions:
what is the sum of interest only product for 2013 and 2014?
what is the sum including 2015?
what is the sum divided by 3?

Answers:
3386
5410
1803.3