The company is reporting our fourth quarter results on a pre-tax basis due to the following factors: One, management has concluded that the company has not remediated its previously disclosed material weakness in internal controls over financial reporting for income taxes relating to current taxes payable, certain deferred tax assets and liabilities, reserves for uncertain tax positions, and current and deferred income tax expense.Second, as a result of the continued material weakness over the accounting for income taxes, significant incremental work has been performed by Weatherford employees and external advisors during 2011 and early 2012, which management expects to result in roughly $225 million to $250 million of aggregate net adjustments to previously reported financial results for the years 2010 and prior relating to the correction of errors identified with respect to the company's accounting for income taxes. Of this total amount, we currently estimate that roughly two-thirds is attributable to fiscal years ending on or prior to December 31, 2008, although management's analysis is not complete. None of the adjustments is expected to affect the company's historically reported net debt balances. Based upon additional analysis and other post-closing procedures, designed to ensure that the company's consolidated financial statements will be presented in accordance with GAAP, the company believes the review of the company's historical tax accounts has been comprehensive and that the process undertaken has been thorough. Until we have concluded work on the above-mentioned adjustments, we will not finalize the company's tax accounts for the year ended December 31, 2011. However, we currently estimate that our income tax expense for the 2011 fiscal year will be between $490 million and $520 million, including credits and charges. This is for 2011 only and does not include the estimated impact of adjustments for 2010 and prior years mentioned above. Our actual cash taxes paid in 2011 were approximately $300 million or 33% of non-GAAP earnings before tax.
The review of the income tax accounts is ongoing among the company, its advisors and the company's auditors. Once finalized, we expect to record the adjustments in the proper historical periods in the audited financial statements to be filed with our 10-K for the year ended December 31, 2011. We plan to file this as soon as practicable.A few important points I'd like to make about our perspective on the income tax issues and the benefits with the process. The process undertaken and the conclusions once finalized are progressed. As mentioned above, the process has been both comprehensive and thorough. Approximately two-thirds of the estimated adjustments in terms of dollar value relates to periods ending on or prior to December 31, 2008. A meaningful portion of the total estimated adjustments relates to reserves for uncertain tax positions that had not been identified or considered prior to us undertaking this process. There are not historical tax cash implications as a result of the adjustments. The company will continue to actively manage its worldwide tax risks to minimize cash tax outlays. The process has produced a better understanding of the value and value drivers of a multinational tax structure. It's a good structure. We'll apply these learnings as we move forward to harvest the structure's value to the company and its shareholders. The results will not be immediate. We expect them to take time and we also expect them to materialize. Moving on to our fourth quarter operational results, today we reported preliminary fourth quarter 2011 pre-tax income of $254 million or $352 million after excluding pre-tax losses of $98 million. The excluded items were composed of a $67 million charge for assets, principally in Libya as well as a $31 million charge for exit, restructuring, investigation and other costs. Fourth quarter revenues of $3.7 billion were the highest in the company's history. Revenues were 10% higher sequentially and up 27% versus the same period last year. North America revenue was up 5% sequentially and up 34% versus the fourth quarter of 2010. International revenues outshined North America, up 15% sequentially and up 21% versus the same quarter of 2010. Artificial Lift, Drilling Services, Integrated Drilling and Stimulation and Chemicals, all posted strong sequential growth. Read the rest of this transcript for free on seekingalpha.com