CÔNG THỨC EXCEL 2003
John Walkenbach F ORMULAS E XCEL 2003 “Mr. Spreadsheet,” author of Excel Charts Includes Power Utility Pak trial and over 90 sample workbooks on CD-ROM Microsoft ® Office E 2003 Excel 2003 Formulas Excel 2003 Formulas John Walkenbach Excel 2003 Formulas Published by Wiley Publishing, Inc. 10475 Crosspoint Boulevard Indianapolis, IN 46256 www.wiley.com Copyright © 2004 by Wiley Publishing, Inc., Indianapolis, Indiana Published by Wiley Publishing, Inc., Indianapolis, Indiana Published simultaneously in Canada ISBN: 0-7645-4073-4 Manufactured in the United States of America 10 9 8 7 6 5 4 3 2 1 1B/QS/RQ/QT/IN No part of this publication may be reproduced, stored in a retrieval system or transmitted in any form or by any means, electronic, mechanical, photocopying, recording, scanning or otherwise, except as permitted under Sections 107 or 108 of the 1976 United States Copyright Act, without either the prior written permission of the Publisher, or authorization through payment of the appropriate per-copy fee to the Copyright Clearance Center, 222 Rosewood Drive, Danvers, MA 01923, (978) 750-8400, fax (978) 646-8600. 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About the Author John Walkenbach is a leading authority on spreadsheet software, and principal of JWalk and Associates Inc., a Southern California–based consulting firm that spe- cializes in spreadsheet application development. John is the author of about 30 spreadsheet books, and has written more than 300 articles and reviews for a variety of publications, including PC World, InfoWorld, PC Magazine, Windows, and PC/Computing. He also maintains a popular Internet Web site (The Spreadsheet Page, www.j-walk.com/ss), and is the developer of the Power Utility Pak, an award-winning add-in for Microsoft Excel. John graduated from the University of Missouri, and earned a Masters and PhD from the University of Montana. Credits ACQUISITIONS EDITOR Greg Croy PROJECT EDITOR Paul Levesque TECHNICAL EDITOR Doug Sahlin COPY EDITOR Jean Rogers EDITORIAL MANAGER Kevin Kirschner VICE PRESIDENT & EXECUTIVE GROUP PUBLISHER Richard Swadley VICE PRESIDENT AND EXECUTIVE PUBLISHER Bob Ipsen VICE PRESIDENT AND PUBLISHER Joseph B. Wikert EXECUTIVE EDITORIAL DIRECTOR Mary Bednarek PROJECT COORDINATOR Ryan Steffen GRAPHICS AND PRODUCTION SPECIALISTS Beth Brooks Carrie Foster Lauren Goddard Joyce Haughey Michael Kruzil Kristin McMullan Erin Zeltner QUALITY CONTROL TECHNICIANS John Greenough Susan Moritz Carl Pierce PERMISSIONS EDITOR Carmen Krikorian MEDIA DEVELOPMENT SPECIALIST Travis Silvers PROOFREADING AND INDEXING TECHBOOKS Production Services Preface Thanks for buying my book. If you’re interested in developing killer formulas and taking Excel to a new level, this book is as good as it gets. I’m confident that you’ll agree that your money was invested wisely. Why I Wrote This Book I approached this project with one goal in mind: To write the ultimate Excel book that would appeal to a broad base of users. That’s a fairly ambitious goal. But based on the feedback I received from the first two editions, I think I’ve accomplished it. I’ve been using Excel for nearly a decade, and I also spend a lot of time partici- pating in the Excel newsgroups on the Internet. As a result, I’m very familiar with the types of questions that come up time and time again. Much of the material in this book was inspired by questions on the Excel newsgroups. This book provides the answers to those questions — along with answers to questions that probably never occurred to you! As you probably know, most bookstores offer dozens of Excel books. The vast majority of these books are general-purpose user guides that explain how to use the features available in Excel (often by simply rewording the text in the help files). A few others focus on advanced issues such as macro programming or scientific applications. None (that’s right, none!) hones in on the one fundamental compo- nent of Excel that is critically important to every user: formulas. Fact is, formulas are what make a spreadsheet a spreadsheet. The more you know about formulas, the better your spreadsheets will be. It’s that simple. Excel is the spreadsheet market leader, by a long shot. This is the case not only because of Microsoft’s enormous marketing clout, but because it is truly the best spreadsheet available. One area in which Excel’s superiority is most apparent is for- mulas. Excel has some special tricks up its sleeve in the formulas department. As you’ll see, Excel lets you do things with formulas that are impossible with other spreadsheets. It’s a safe bet that only about ten percent of Excel users really understand how to get the most out of worksheet formulas. In this book, I attempt to nudge you into that elite group. Are you up to it? What You Should Know This is not a book for beginning Excel users. If you have absolutely no experience with Excel, this may not be the best book for you — unless you’re one of a rare breed who can learn a new software product almost instantaneously. vii To get the most out of this book, you should have some background using Excel. Specifically, I assume that you know how to ◆ Create workbooks, insert sheets, save files, and other basic tasks ◆ Navigate through a workbook ◆ Use Excel’s menus, toolbars, and dialog boxes ◆ Use basic Windows features, such as file management and copy and paste techniques If you’re an experienced spreadsheet user,but you are new to Excel, Chapter 1 presents a concise overview of what this product has to offer. What You Should Have To make the best use of this book, you need a copy of Microsoft Excel. When I wrote the current edition of the book, I was using Excel 2003 (which is part of Microsoft Office 2003). With a few exceptions (noted in the text), the material in this book also applies to all earlier versions of Excel that are still in use. To use the examples on the companion CD-ROM, you’ll need a CD-ROM drive. The examples on the CD-ROM are discussed further in the “About the Companion CD-ROM” section, later in this preface. I use Excel for Windows exclusively,and I do not own a Macintosh.Therefore, I can’t guarantee that all of the examples will work with Excel for Macintosh. Excel’s cross-platform compatibility is pretty good, but it’s definitely not perfect. As far as hardware goes, the faster the better. And, of course, the more memory in your system, the happier you’ll be. And, I strongly recommend using a high- resolution video mode: at least 1024 x 768. Conventions in This Book Take a minute to skim this section and learn some of the typographic conventions used throughout this book. viii Preface [...]... =sum(a1:a50) Excel, however, will convert the characters in the second formula to uppercase Mouse Conventions The mouse terminology in this book is all standard fare: “pointing,” “clicking,” “right-clicking,” “dragging,” and so on You know the drill What the Icons Mean Throughout the book, icons appear to call your attention to points that are particularly important This icon indicates a feature new to Excel 2003. .. xv Part I Basic Information Chapter 1 Excel in a Nutshell 3 The History of Excel 4 It Started with VisiCalc 4 Then Came Lotus 4 Microsoft Enters the Picture 4 Excel Versions 5 The Object... appear on a separate line in monospace font For example, I may list the following formula: =VLOOKUP(StockNumber,PriceList,2,False) Excel supports a special type of formula known as an array formula When you enter an array formula, press Ctrl+Shift+Enter (not just Enter) Excel encloses an array formula in brackets in order to remind you that it’s an array formula When I list an array formula, I include... find helpful Part I: Basic Information This part is introductory in nature, and consists of Chapters 1 through 3 Chapter 1 sets the stage with a quick and dirty overview of Excel This chapter is designed for readers who are new to Excel, but who have used other spreadsheet products In Chapter 2, I cover the basics of formulas This chapter is absolutely essential reading in order to get the most out of... computer book without appendixes? This book has five appendixes In the appendixes, you’ll find secrets about importing 1-2-3 files, a quick reference guide to Excel s worksheet functions, tips on using custom number formats, and a handy guide to Excel resources on the Internet The final appendix describes all the files on the CD-ROM How to Use This Book You can use this book any way you please If you... can redeem for a discounted copy of my award-winning Power Utility Pak — a collection of useful Excel utilities, plus many new worksheet functions I developed this package using VBA exclusively You can also use this coupon to purchase the complete VBA source code for a nominal fee Studying the code is an excellent way to pick up some useful programming techniques You can take the product for a test... “typical” Excel book, and publishing it was a risky venture The risk paid off, however, as evidenced by the fact that it is now in its third edition Special thanks to Paul Levesque, my project editor He made my job much easier xv Contents at a Glance Preface vii Acknowledgments xv Part I Basic Information Chapter 1 Chapter 2 Chapter 3 Excel in... 597 609 629 663 Appendix A: Working with Imported 1-2-3 Files 709 Appendix B: Excel Function Reference 717 Appendix C: Using Custom Number Formats 735 Appendix D: Additional Excel Resources 761 Appendix E: What’s on the CD-ROM 769 Index 783 End-User License Agreement... RANGES Excel s worksheet functions appear in all uppercase, like so: “Use the SUM function to add the values in column A.” Macro and procedure names appear in normal type: “Execute the InsertTotals procedure.” I often use mixed upper- and lowercase to make these names easier to read Named ranges appear in italic: “Select the InputArea range.” Unless you’re dealing with text inside of quotation marks, Excel. .. Errors 588 Using Background Error Checking 588 Using Excel s Formula Evaluator 590 Third-Party Auditing Tools 591 Power Utility Pak 591 Spreadsheet Detective 592 Excel Auditor 593 xxxi xxxii Contents Part VI Developing Custom