Loss on Early Extinguishment of Debt Interest Expense Income Tax Expense Segment Analysis 21 The following charts and tables summarize the operating results for our three complementary business segments. Income tax expense increased $9.1 million in 2013 compared to 2012 due primarily to an increase in taxable income in 2013. Income  tax expense increased $17.7 million in 2012 compared to 2011 primarily due to the reversal in 2011 of $10.4 million in tax liabilities  provided over the period 2007-2010 as a result of concluded audits of prior year returns, differences between recently filed tax returns  and the estimates included in our tax provisions and an increase in taxable income in 2012. The effective tax rate was 25.0% for 2013,  24.9% for 2012 and 22.7% for 2011. Interest expense increased by $0.5 million in 2013 compared to 2012 primarily due to increased borrowings on our revolving Credit  Facility. Interest expense decreased during 2012 as our $150 million Senior Notes carry a lower interest rate than the Exchangeable  Notes which were fully repaid and extinguished during 2011. In 2006, Core Laboratories LP, an entity 100% indirectly owned by Core Laboratories N.V., issued $300 million aggregate principal amount of Senior Exchangeable Notes (the “Exchangeable Notes”) which were fully and unconditionally guaranteed by Core  Laboratories N.V. and matured on October 31, 2011. During 2011, 156,301 Exchangeable Notes were extinguished resulting in a loss of $1.0 million.  Production Enhancement 42% Reservoir Management 9% Reservoir Description 49% Production Enhancement 41% Reservoir Management 8% Reservoir Description 51% Production Enhancement 41% Reservoir Management 7% Reservoir Description 52% 2013 Revenues by Segment 2012 Revenues by Segment 2011 Revenues by Segment