depending upon our senior unsecured debt ratings .
the facilities require the maintenance of a minimum net worth and a debt to net worth coverage ratio .
at december 31 , 2006 , we were in compliance with these covenants .
the facilities do not include any other financial restrictions , credit rating triggers ( other than rating-dependent pricing ) , or any other provision that could require the posting of collateral .
in addition to our revolving credit facilities , we had $ 150 million in uncommitted lines of credit available , including $ 75 million that expires in march 2007 and $ 75 million expiring in may 2007 .
neither of these lines of credit were used as of december 31 , 2006 .
we must have equivalent credit available under our five-year facilities to draw on these $ 75 million lines .
dividend restrictions 2013 we are subject to certain restrictions related to the payment of cash dividends to our shareholders due to minimum net worth requirements under the credit facilities referred to above .
the amount of retained earnings available for dividends was $ 7.8 billion and $ 6.2 billion at december 31 , 2006 and 2005 , respectively .
we do not expect that these restrictions will have a material adverse effect on our consolidated financial condition , results of operations , or liquidity .
we declared dividends of $ 323 million in 2006 and $ 316 million in 2005 .
shelf registration statement 2013 under a current shelf registration statement , we may issue any combination of debt securities , preferred stock , common stock , or warrants for debt securities or preferred stock in one or more offerings .
at december 31 , 2006 , we had $ 500 million remaining for issuance under the current shelf registration statement .
we have no immediate plans to issue any securities ; however , we routinely consider and evaluate opportunities to replace existing debt or access capital through issuances of debt securities under this shelf registration , and , therefore , we may issue debt securities at any time .
6 .
leases we lease certain locomotives , freight cars , and other property .
future minimum lease payments for operating and capital leases with initial or remaining non-cancelable lease terms in excess of one year as of december 31 , 2006 were as follows : millions of dollars operating leases capital leases .

<i>Millions of Dollars</i>
<i>OperatingLeases</i>
Capital Leases
2007
$624
$180
2008
546
173
2009
498
168
2010
456
148
2011
419
157
Later Years
2,914
1,090
Total minimum lease payments
$5,457
$1,916
Amount representing interest
N/A
(680)
Present value of minimum lease payments
N/A
$1,236

rent expense for operating leases with terms exceeding one month was $ 798 million in 2006 , $ 728 million in 2005 , and $ 651 million in 2004 .
when cash rental payments are not made on a straight-line basis , we recognize variable rental expense on a straight-line basis over the lease term .
contingent rentals and sub-rentals are not significant. .

Question: Analyse this data from a financial earnings document. what percentage of total minimum lease payments are capital leases as of december 31 , 2006?
Choices:
0.25987
0.16764
0.54109
0.39669
0.28627
Correct choice index: 0