Interest expense was lower, principally reflecting the redemption of debt at the beginning of the year, giving adjusted pretax profit up 11% in sterling and at constant currencies. In euros, there were up 18%.
The effective tax rate was up 40 basis points, reflecting increased profit and geographic mix. Adjusted net profit was up 11% in sterling and 10% at constant currencies. The increase in euros was 18%.
Focusing on revenue, profit and margin. As said earlier, underlying revenue growth was 5% and operating profit -- underlying operating profit growth was 7%, with each of our businesses contributing underlying revenue and profit growth.
The 110 basis points increase in operating margin included 40 basis points from portfolio change, including the effect of low margin disposals in the prior year, as well as this year. The margin increase also included 10 basis points from currency effects, with a positive impact from the multiyear subscription currency hedging program in Elsevier, mostly offset by unfavorable currency translation mix effects. The impact of currency hedging and translation effects in Elsevier is set out in the appendix. The underlying margin improvement to 60 basis points reflects the revenue growth and improvement in operating efficiency, while we continue to invest in new product initiatives, sales and marketing and market expansion.Our 5% underlying revenue growth came from Elsevier, up 2%, resolutions up 5%, legal and professional up 1%, Reed Exhibitions up 23%, and RBI up 1%. The difference between the underlying change and the constant rate changes reflects acquisitions and disposals. Read the rest of this transcript for free on seekingalpha.com