$4 billion: Amount paid by Houghton Mifflin Riverdeep to acquire Harcourt's U.S. School Education Group from Reed Elsevier$1.11 billion: Revenue of properties sold11.8: Percent stake Reed will have in new HM Riverdeep3.6: Ratio of purchase price to revenue3.3: Ratio of purchase price to revenue of Apax Partners and the OMERS pension fund acquisition of Thomson Learning2.6: Ratio of purchase price, including debt assumption, of Riverdeep's acquisition of Houghton Mifflin$5.65 billion: Price Reed paid, including debt assumption, for Harcourt General in 2000$2.06 billion: Price Thomson paid to Reed Elsevier for Harcourt higher education and professional divisions in 2000$2.41 billion: Estimated combined sales of HM, Harcourt school publishing operations2: HM/Harcourt's rank among U.S. school publishers$200 million: Estimated sales of combined HM, Harcourt trade publishing operations7,500: Combined number of trade titles published by HM, Harcourt