DEBT

A summary of long-term debt is as follows:



	September 30,
(In thousands)	2015		2014
Senior Notes 6.5% due 2020 ("Senior Notes")	$	655,946	$	657,122
Revolving Credit Facility	1,030,000		1,085,000
Total long-term debt	$	1,685,946	$	1,742,122

Senior Notes

As of September 30, 2015, our Senior Notes had aggregate principal amount of $650 million. Our Senior Notes are unsecured obligations and are not guaranteed by any of our subsidiaries. We received a premium of $8.5 million as part of the net proceeds for the Senior Notes issued in 2013. This premium is being amortized over the life of our Senior Notes.

Revolving Credit Facility

As of September 30, 2015, our revolving credit facility (the "Credit Facility"), had $1.547 billion of total commitments. Our wholly-owned subsidiary, Atwood Offshore Worldwide Limited (“AOWL”), is the borrower under the Credit Facility and we and certain of our other subsidiaries are guarantors under the facility. On March 5, 2015, we entered into an amendment to the credit facility, which, among other things, (i) extended the maturity with respect to $1.245 billion of the total $1.547 billion of commitments under the Credit Facility to May 2019 and (ii) amended the maximum leverage ratio upwards to 4.50:1.00 through December 31, 2017, after which period the maximum leverage ratio will revert back to 4.00:1.00 through maturity. Lenders holding commitments of approximately $305 million did not agree to extend their commitment and those commitments mature in May 2018. On August 6, 2015, total commitments were reduced from $1.550 billion to $1.547 billion due to the sale of the Atwood Hunter which secured the Credit Facility prior to its sale

As of September 30, 2015, we had $1.03 billion of outstanding borrowings and $5.3 million of letters of credit issued under the Credit Facility. As of September 30, 2015, we had approximately $512 million available for borrowings under the Credit Facility. Borrowings under the Credit Facility bear interest at the Eurodollar rate plus a margin ranging from 1.75% to 2.00% and the commitment fee on the unused portion of the underlying commitment ranges from 0.30% to 0.40% per annum, each case based on our corporate credit ratings. The Credit Facility is secured primarily by first preferred mortgages on eight of our active drilling units (Atwood Aurora, Atwood Beacon, Atwood Condor, Atwood Eagle, Atwood Falcon, Atwood Mako, Atwood Manta and Atwood Osprey), as well as liens on the equity interests of our subsidiaries that own, directly or indirectly, such drilling units. We were in compliance with all financial covenants under the Credit Facility at September 30, 2015, and we anticipate that we will continue to be in compliance for the next fiscal year.

On July 29, 2015, we entered into an amendment to our Credit Facility, providing that, among other things, effective upon our obtaining a specified amount of additional unsecured capital through one or more qualifying capital raises and a subsequent permanent reduction in the commitments under the Credit Facility in an amount equal to at least 70% of the net proceeds from such capital raises, (i) the maximum leverage ratio will be replaced with a senior secured leverage ratio of 3.0:1.0 and (ii) the minimum interest expense coverage ratio will be reduced from 3.0% to 1.0% to 1.75% to 1.00%. The minimum collateral maintenance of 150% of the aggregate amount outstanding under the Credit Facility remains unchanged.

Letter of Credit Facility

On July 29, 2015, our subsidiary AOWL, entered into a letter of credit facility with BNP Paribas (“BNP”), pursuant to which BNP may, in its sole and absolute discretion, issue letters of credit from time to time at the request of AOWL, for the account of AOWL and its subsidiaries, up to an unlimited stated face amount of such letters of credit. Certain fees will be payable upon the issuance of each letter of credit under the letter of credit facility, with the amount of such fees depending on whether such letters of credit are performance letters of credit or financial letters of credit. BNP has no commitment under the facility to issue letters of credit, and the facility, as well as BNP’s willingness to receive requests from AOWL with respect to the issuance of letters of credit may be cancelled by BNP at any time. The facility contains certain events of default, including but not limited to delinquent payments, bankruptcy filings, material adverse judgments, cross-defaults under other debt agreements, or a change of control.

The weighted-average effective interest rate on our long-term debt during fiscal years 2015 and 2014 was 2.60% and 2.28%, respectively. The effective rate was determined after giving consideration to the effect of our interest rate swaps accounted for as hedges and the amortization of premiums or discounts. Interest expense for fiscal years 2015, 2014 and 2013 was $52.6 million, $41.8 million and $24.9 million, respectively. Capitalized interest expense for fiscal 2015, 2014 and 2013 was $22.2 million, $30.0 million and $33.2 million, respectively.