impairment at the reporting unit (Security Systems Division) level. The result of the June 2009 test of recoverability of long lived assets associated with the UK passport activity indicated that the asset grouping’s carrying amount of approximately $54 million (before impairment) exceeded the remaining expected cash flows. Accordingly, 3M recorded a non-cash impairment charge of approximately $13 million in the second quarter of 2009 to write these assets down to their fair value. In addition, accelerated depreciation/amortization was taken over the period June 2009 through the date of expiration of the contract based on a reassessment of the remaining expected useful life of these assets.

 

3M goodwill totaled approximately $7.0 billion as of December 31, 2011. 3M’s annual goodwill impairment testing is performed in the fourth quarter of each year. Impairment testing for goodwill is done at a reporting unit level, with all goodwill assigned to a reporting unit. Reporting units are one level below the business segment level (3M has six business segments at December 31, 2011), but can be combined when reporting units within the same segment have similar economic characteristics. At 3M, reporting units generally correspond to a division. 3M did not combine any of its reporting units for impairment testing.

 

An impairment loss generally would be recognized when the carrying amount of the reporting unit’s net assets exceeds the estimated fair value of the reporting unit. The estimated fair value of a reporting unit is determined using earnings for the reporting unit multiplied by a price/earnings ratio for comparable industry groups, or by using a discounted cash flow analysis. 3M typically uses the price/earnings ratio approach for stable and growing businesses that have a long history and track record of generating positive operating income and cash flows. 3M uses the discounted cash flow approach for start-up, loss position and declining businesses, but also uses discounted cash flow as an additional tool for businesses that may be growing at a slower rate than planned due to economic or other conditions.

 

As discussed in Note 17 to the Consolidated Financial Statements, effective in the first quarter of 2011, 3M made certain product moves between its business segments. For those changes that resulted in reporting unit changes, the Company applied the relative fair value method to determine the impact to reporting units. During the first quarter of 2011, the Company completed its assessment of any potential goodwill impairment for reporting units impacted by this new structure and determined that no impairment existed. The discussion that follows relates to the separate fourth quarter 2011 annual impairment test and is in the context of the segment structure that existed at that time.

 

As of September 30, 2011, 3M had 38 primary reporting units, with ten reporting units accounting for approximately 76 percent of the goodwill. These ten reporting units were comprised of the following divisions: 3M Purification Inc., Occupational Health and Environmental Safety, Optical Systems, Infection Prevention, Security Systems, 3M