The "USAF Statistical Digest" summarizes in one document selected statistical data collected and published by various offices in Headquarters, United States Air Force and certain major commands. It is published in accordance with AFR 5-24 and is to be used as the official basic reference document for the period and areas covered. This is the fourteenth edition in an annual series which began in 1946. A 1945 edition, "Army Air Force Statistical Digest (World War II)" and "Supplement 1" summarized data on World War II and on selected subjects for 1945. In each edition an effort has been made to preserve the continuity of data in order to facilitate comparison and analysis. General information pertaining to specific subject-matter areas and definitions of terms used can be found in the introductory statements of each part. The subject-matter subdivisions of this volume have been reorganized but the sequence of the material is essentially similar to the Fiscal Year 1958 edition. Prior year data which had been included in some tables has been eliminated. Sources of data are the published and unpublished records of the Directorate of Statistical Services, except as otherwise noted in the source credit after each table.