Fourth quarter 2009 results were favorably impacted by certain net additions, after tax, totaling $10 million, or $0.03 per diluted share, as follows:
- $34 million for the gain on sale of an interest in a joint venture,
- $24 million of income related to the settlement of litigation matters,
- Partially offset by $48 million of net charges primarily related to discrete tax items, the retirement of debt and adjustments associated with the GlobalSantaFe merger.
For the year ended December 31, 2009, net income attributable to controlling interest totaled $3.181 billion, or $9.84 per diluted share, on revenues of $11.556 billion. Net income for the year ended December 31, 2009 included after-tax charges of $498 million, or $1.55 per diluted share, resulting primarily from the fourth quarter items listed above, in addition to charges earlier this year of $334 million on impairments of intangible assets and two rigs held for sale, $132 million on litigation matters and $42 million of net charges primarily related to discrete tax items, the retirement of debt and adjustments associated with the GlobalSantaFe merger.
For 2008, net income attributable to controlling interest was $4.031 billion, or $12.53 per diluted share, on revenues of $12.674 billion. Net income for the year ended December 31, 2008 included after-tax charges of $401 million, or $1.24 per diluted share, primarily related to impairments of goodwill and other intangible assets, write-downs of two rigs held for sale and additional depreciation, depletion and amortization expense resulting from an adjustment to the useful lives of certain rigs acquired in the GlobalSantaFe merger.
Operations Quarterly Review
Revenues for the three months ended December 31, 2009 decreased to $2.733 billion, compared to revenues of $2.823 billion during the three months ended September 30, 2009. The decrease was primarily due to a $219 million reduction in revenue resulting from the stacking of rigs and reduced revenue efficiency, partially offset by a $136 million increase in revenue due to the commencement of operations of three of our newbuild drillships and improvement in average dayrates for floaters.
Operating and maintenance expenses totaled $1.296 billion for the fourth quarter 2009, down seven percent compared to $1.396 billion for the prior quarter. The $100 million quarter-to-quarter reduction in operating and maintenance costs occurred as a result of $137 million in litigation settlement expenses in the third quarter 2009 and a $24 million favorable impact from litigation settlements in the fourth quarter 2009. These items were partially offset by shipyard extensions, increases in maintenance projects and commencement of operations of our newbuilds. In addition, the fourth quarter was favorably impacted by $43 million of reduced costs from stacked rigs and negatively impacted by unplanned costs of $28 million due to an operational incident affecting a jackup.
Depreciation, depletion and amortization expense was $382 million in the fourth quarter 2009, up four percent versus $367 million for the third quarter 2009. The increase was due to the impact on depreciation in the fourth quarter of 2009 from the commencement of operations of the newbuild units, compared to the prior quarter.
General and administrative expenses were $46 million for the fourth quarter 2009 compared to $54 million in the prior quarter. The $8 million decrease was due, in part, to reduced year-end accruals related to one-time personnel expenses.
Liquidity and Interest Expense
Interest expense, net of amounts capitalized for the fourth quarter 2009, increased to $119 million compared to $115 million in the third quarter 2009. The increase was due to the impact of two months of interest expense in the third quarter 2009 compared to the full quarter of interest expense in the fourth quarter 2009 for the Petrobras 10000 capital lease. As of December 31, 2009, total debt was $11.7 billion, compared to $11.9 billion as of September 30, 2009.
Cash flow from operating activities decreased to $1.175 billion for the fourth quarter 2009 compared to $1.406 billion for the third quarter 2009. For the full year 2009, cash flow from operating activities totaled $5.598 billion compared to $4.959 billion for the full year 2008.
Effective Tax Rate
Transocean's Annual Effective Tax Rate(1), which excludes various discrete items, for the fourth quarter 2009 and the full year ended December 31, 2009 was 17.4 percent and 16.0 percent, respectively. The Effective Tax Rate(2) for the fourth quarter 2009 and the full year ended December 31, 2009 was 20.1 percent and 19.2 percent, respectively. Transocean's Effective Tax Rate reflects the impact of changes in estimates as well as the impact of impairments.