While crude oil prices remain well above the levels of a year ago, natural gas prices have shown only a moderate increase relative to 2009. Downstream, chemical margins have improved relative to 2009. However, some chemical margins have weakened recently as a result of new industry capacity coming online.Turning now to the fourth quarter financial results as shown on slide 4, ExxonMobil's fourth quarter 2010 earnings excluding special items were $9.3 billion, an increase of $3.2 billion from the fourth quarter of 2009. Earnings per share for the quarter, excluding special items, were $1.85, up $0.58 from a year ago. The corporation distributed more than $7 billion to shareholders in the fourth quarter through dividends and share purchases to reduce shares outstanding. Of that total, $5 billion was distributed to purchase shares. Share purchases to reduce shares outstanding are expected to be $5 billion in the first quarter of 2011. Cap ex in the fourth quarter was $10.1 billion, up $1.8 billion from the fourth quarter of 2009, primarily due to the addition of XTO. We continue to invest in robust projects through the business cycle to help meet global demand for crude oil, natural gas, and finished products. The effective tax rate in the fourth quarter was 43%. Moving now to the full year results, as shown on slide 5, ExxonMobil's full year 2010 earnings were $30.5 billion, up $11.2 billion from 2009. ExxonMobil's full year 2010 earnings, excluding special items, were also $30.5 billion, up $11 billion from 2009, which included a charge of $140 million for interest related to the Valdez litigation. Earnings per share for the year, excluding special items, were $6.22, up $2.21 from 2009. The corporation distributed $19.7 billion to shareholders in 2010 through dividends and share purchases to reduce shares outstanding. Of that total, $11.2 billion was distributed to purchase shares.
Cap ex in 2010 was $32.2 billion, up $5.1 billion from 2009, mainly due to the addition of XTO and continued progress on our world-class project portfolio, including the Kearl Oil Sands project.Our cash generation remains very strong, with $51.7 billion in cash flow from operations and asset sales. At the end of 2010, our cash balance was $8.5 billion and debt was $15 billion, which reflects the impact of retiring $7.3 billion of XTO debt. We will now provide a review of segmented earnings, starting on slide 6. ExxonMobil earnings increased $3.2 billion from the fourth quarter of 2009, with strong results across all business lines. Upstream earnings increased $1.7 billion, while downstream earnings improved by $1.3 billion and chemical earnings grew by $350 million. Corporate and financing expenses were about $450 million during the quarter, up $190 million versus the fourth quarter of 2009, due mainly to financing activities. As shown on slide 7, ExxonMobil earnings increased $1.9 billion from the third quarter of 2010, mainly due to higher earnings in the upstream, partly offset by slightly lower chemical earnings. Looking now at the full year comparison on slide 8, ExxonMobil's full year 2010 earnings excluding special items were $30.5 billion, up $11 billion from 2009, reflecting strong results in each of our businesses. Upstream earnings increased $7 billion while downstream and chemical earnings were up $1.8 billion and $2.6 billion respectively. Corporate and financing expenses, excluding special items, for the full year in 2010, were $2.1 billion, up $340 million from 2009, due mainly to a charge related to the U.S. healthcare legislation and financing activities. The average quarterly corporate and financing expense in 2010 was $530 million, consistent with our continued guidance of $500 million to $700 million per quarter. Moving next to the upstream results, and beginning on slide 9, ExxonMobil continues to make excellent progress on its global portfolio of high quality liquids projects. Our recent startup at Odoptu performed extremely well during the quarter, averaging more than 50,000 barrels per day of liquids production.
We also recently set a new world record for extended reach drilling on the Odoptu OP-11 well. Employing ExxonMobil's proprietary drilling capabilities, this well reached a total measured depth of 12,345 meters, or over 7.5 miles, with a horizontal reach of 11,475 meters, and was completed in only 60 days.Read the rest of this transcript for free on seekingalpha.com