2012, 2011, and 2010. In 2012, 2011, and 2010, the amounts primarily related to amortization of intangible assets. 

Income from Operations 

For the reasons discussed above, income from operations decreased 22% in 2012, decreased 39% in 2011, and increased 25% in 2010. 

Interest Income and Expense 

Our interest income was $40 million, $61 million, and $51 million during 2012, 2011, and 2010. We generally invest our excess cash in investment grade short- to intermediate-term fixed income securities and AAA-rated money market funds. Our interest income corresponds with the average balance of invested funds and the prevailing rates we are earning on them, which vary depending on the geographies and currencies in which they are invested. 

The primary component of our interest expense is related to our long-term debt and capital and financing lease arrangements. Interest expense was $92 million, $65 million, and $39 million in 2012, 2011, and 2010. 

Our long-term debt was $3.1 billion and $255 million at December 31, 2012 and 2011. Our other long-term liabilities were $2.3 billion and $2.4 billion at December 31, 2012 and 2011. See Item 8 of Part II, “Financial Statements and Supplementary Data—Note 6—Long-Term Debt and Note 7—Other Long-Term Liabilities” for additional information. 

Other Income (Expense)

Other income (expense), net was $(80) million, $76 million, and $79 million during 2012, 2011, and 2010. The primary component of other income (expense), net, is related to foreign-currency gains (losses) on intercompany balances. 

Income Taxes 

Our effective tax rate is subject to significant variation due to several factors, including variability in our pre-tax and taxable income and loss and the mix of jurisdictions to which they relate, changes in how we do business, acquisitions (including integrations) and investments, audit developments, foreign currency gains (losses), changes in law, regulations, and administrative practices, and relative changes of expenses or losses for which tax benefits are not recognized. 

We recorded a provision for income taxes of $428 million, $291 million, and $352 million in 2012, 2011, and 2010. Our effective tax rate in 2012, 2011, and 2010 is significantly affected by two factors: the favorable impact of earnings in lower tax rate jurisdictions and the adverse effect of losses incurred in certain foreign jurisdictions for which we may not realize a tax benefit. Income earned in lower tax jurisdictions is primarily related to our European operations, which are headquartered in Luxembourg. Losses incurred in foreign jurisdictions for which we may not realize a tax benefit, primarily generated by subsidiaries located outside of Europe, reduce our pre-tax income without a corresponding reduction in our tax expense, and therefore increase our effective tax rate. We have recorded a valuation allowance against the related deferred tax assets. 

In 2012, the adverse impact of such foreign jurisdiction losses was partially offset by the favorable impact of earnings in lower tax rate jurisdictions. Additionally, our effective tax rate in 2012 was more volatile as compared to prior years due to the lower