the environmental liability includes costs for remediation and restoration of sites , as well as for ongoing monitoring costs , but excludes any anticipated recoveries from third parties .
cost estimates are based on information available for each site , financial viability of other potentially responsible parties , and existing technology , laws , and regulations .
we believe that we have adequately accrued for our ultimate share of costs at sites subject to joint and several liability .
however , the ultimate liability for remediation is difficult to determine because of the number of potentially responsible parties involved , site-specific cost sharing arrangements with other potentially responsible parties , the degree of contamination by various wastes , the scarcity and quality of volumetric data related to many of the sites , and the speculative nature of remediation costs .
estimates may also vary due to changes in federal , state , and local laws governing environmental remediation .
we do not expect current obligations to have a material adverse effect on our results of operations or financial condition .
guarantees 2013 at december 31 , 2006 , we were contingently liable for $ 464 million in guarantees .
we have recorded a liability of $ 6 million for the fair value of these obligations as of december 31 , 2006 .
we entered into these contingent guarantees in the normal course of business , and they include guaranteed obligations related to our headquarters building , equipment financings , and affiliated operations .
the final guarantee expires in 2022 .
we are not aware of any existing event of default that would require us to satisfy these guarantees .
we do not expect that these guarantees will have a material adverse effect on our consolidated financial condition , results of operations , or liquidity .
indemnities 2013 our maximum potential exposure under indemnification arrangements , including certain tax indemnifications , can range from a specified dollar amount to an unlimited amount , depending on the nature of the transactions and the agreements .
due to uncertainty as to whether claims will be made or how they will be resolved , we cannot reasonably determine the probability of an adverse claim or reasonably estimate any adverse liability or the total maximum exposure under these indemnification arrangements .
we do not have any reason to believe that we will be required to make any material payments under these indemnity provisions .
income taxes 2013 as previously reported in our form 10-q for the quarter ended september 30 , 2005 , the irs has completed its examinations and issued notices of deficiency for tax years 1995 through 2002 .
among their proposed adjustments is the disallowance of tax deductions claimed in connection with certain donations of property .
in the fourth quarter of 2005 , the irs national office issued a technical advice memorandum which left unresolved whether the deductions were proper , pending further factual development .
we continue to dispute the donation issue , as well as many of the other proposed adjustments , and will contest the associated tax deficiencies through the irs appeals process , and , if necessary , litigation .
in addition , the irs is examining the corporation 2019s federal income tax returns for tax years 2003 and 2004 and should complete their exam in 2007 .
we do not expect that the ultimate resolution of these examinations will have a material adverse effect on our consolidated financial statements .
11 .
other income other income included the following for the years ended december 31 : millions of dollars 2006 2005 2004 .

<i>Millions of Dollars</i>
2006
2005
2004
Rental income
$83
$59
$55
Net gain on non-operating asset dispositions
72
135
69
Interest income
29
17
10
Sale of receivables fees
(33)
(23)
(11)
Non-operating environmental costs and other
(33)
(43)
(35)
Total
$118
$145
$88

.

Question: Analyse this data from a financial earnings document. what was the percentage change in rental income from 2004 to 2005?
Choices:
0.07273
0.0678
-0.11429
13.75
4
Correct choice index: 0