Chapter 1: Excel in a Nutshell 3 Chapter 2: Basic Facts about Formulas 33 Chapter 3: Working with Names 59

Transcription

1 Contents at a Glance Part I: Basic Information Chapter 1: Excel in a Nutshell 3 Chapter 2: Basic Facts about Formulas 33 Chapter 3: Working with Names 59 Part II: Using Functions in Your Formulas Chapter 4: Introducing Worksheet Functions 99 Chapter 5: Manipulating Text 115 Chapter 6: Working with Dates and Times 139 Chapter 7: Counting and Summing Techniques 177 Chapter 8: Using Lookup Functions 211 Chapter 9: Tables and Worksheet Databases 233 Chapter 10: Miscellaneous Calculations 277 Part III: Financial Formulas Chapter 11: Borrowing and Investing Formulas 295 Chapter 12: Discounting and Depreciation Formulas 321 Chapter 13: Financial Schedules 347 Part IV: Array Formulas Chapter 14: Introducing Arrays 375 Chapter 15: Performing Magic with Array Formulas 399 Part V: Miscellaneous Formula Techniques Chapter 16: Intentional Circular References 429 Chapter 17: Charting Techniques 443 Chapter 18: Pivot Tables 485 Chapter 19: Conditional Formatting and Data Validation 527 Chapter 20: Creating Megaformulas 563 Chapter 21: Tools and Methods for Debugging Formulas 581 COPYRIGHTED MATERIAL

2 viii Excel 2007 Formulas Part VI: Developing Custom Worksheet Functions Chapter 22: Introducing VBA 607 Chapter 23: Function Procedure Basics 623 Chapter 24: VBA Programming Concepts 645 Chapter 25: VBA Custom Function Examples 679 Part VII: Appendixes Appendix A: Excel Function Reference 727 Appendix B: Using Custom Number Formats 745 Appendix C: Additional Excel Resources 767 Appendix D: What s on the CD-ROM 773 Index 783

3 Table of Contents Why I Wrote This Book What You Should Know What You Should Have Conventions in This Book Keyboard Conventions Mouse Conventions What the Icons Mean How This Book Is Organized Part I: Basic Information Part II: Using Functions in Your Formulas Part III: Financial Formulas Part IV: Array Formulas Part V: Miscellaneous Formula Techniques Part VI: Developing Custom Worksheet Functions Part VII: Appendixes How to Use This Book About the Companion CD-ROM About the Power Utility Pak Offer Reach Out xxv xxv xxv xxvi xxvi xxvii xxvii xxviii xxviii xxix xxix xxix xxix xxix xxix xxx xxx xxx xxxi 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 5 Excel Versions 5 The Object Model Concept 8 The Workings of Workbooks 8 Worksheets 9 Chart Sheets 10 Macro Sheets and Dialog Sheets 10 The Excel User Interface 12 A New User Interface 12 The Ribbon 12 The Office Button Menu 14 Shortcut Menus and the Mini Toolbar 15 The Quick Access Toolbar 16

4 x Excel 2007 Formulas Smart Tags 16 Task Pane 17 Drag and Drop 17 Keyboard Shortcuts 18 Customized Onscreen Display 18 Data Entry 19 Object and Cell Selecting 19 The Excel Help System 21 Cell Formatting 22 Numeric Formatting 22 Stylistic Formatting 22 Tables 23 Worksheet Formulas and Functions 23 Objects on the Drawing Layer 24 Shapes 24 Illustrations 24 Linked Picture Objects 25 Controls 25 Charts 26 Customization in Excel 26 Macros 26 Add-in Programs 26 Internet Features 27 Analysis Tools 27 Database Access 27 Outlines 29 Scenario Management 29 Pivot Tables 29 Auditing Capabilities 30 Solver Add-in 30 Protection Options 30 Protecting Formulas from Being Overwritten 30 Protecting a Workbook s Structure 31 Password-protecting a Workbook 32 Chapter 2: Basic Facts about Formulas 33 Entering and Editing Formulas 34 Formula Elements 34 Entering a Formula 34 Pasting Names 36 Spaces and Line Breaks 36 Formula Limits 37 Sample Formulas 37 Editing Formulas 38 Using Operators in Formulas 39 Reference Operators 40 Sample Formulas That Use Operators 40 Operator Precedence 41 Nested Parentheses 42

5 Table of Contents xi Calculating Formulas 44 Cell and Range References 45 Creating an Absolute or a Mixed Reference 45 Referencing Other Sheets or Workbooks 48 Making an Exact Copy of a Formula 48 Converting Formulas to Values 49 Hiding Formulas 51 Errors in Formulas 52 Dealing with Circular References 53 Goal Seeking 55 A Goal Seeking Example 55 More about Goal Seeking 57 Chapter 3: Working with Names 59 What s in a Name? 60 A Name s Scope 61 Referencing Names 61 Referencing Names from Another Workbook 62 Conflicting Names 62 The Name Manager 62 Creating Names 63 Editing Names 64 Deleting Names 64 Shortcuts for Creating Cell and Range Names 65 The New Name Dialog Box 65 Creating Names Using the Name Box 66 Creating Names Automatically 67 Naming Entire Rows and Columns 68 Names Created by Excel 69 Creating Multisheet Names 71 Working with Range and Cell Names 72 Creating a List of Names 73 Using Names in Formulas 73 Using the Intersection Operators with Names 74 Using the Range Operator with Names 76 Referencing a Single Cell in a Multicell Named Range 76 Applying Names to Existing Formulas 76 Applying Names Automatically When Creating a Formula 77 Unapplying Names 78 Names with Errors 78 Viewing Named Ranges 79 Using Names in Charts 79 How Excel Maintains Cell and Range Names 80 Inserting a Row or Column 80 Deleting a Row or Column 80 Cutting and Pasting 80 Potential Problems with Names 80 Name Problems When Copying Sheets 81 Name Problems When Deleting Sheets 82

6 xii Excel 2007 Formulas The Secret to Understanding Names 83 Naming Constants 84 Naming Text Constants 85 Using Worksheet Functions in Named Formulas 86 Using Cell and Range References in Named Formulas 87 Using Named Formulas with Relative References 88 Advanced Techniques That Use Names 91 Using the INDIRECT Function with a Named Range 91 Using the INDIRECT Function to Create a Named Range with a Fixed Address 92 Using Arrays in Named Formulas 93 Creating a Dynamic Named Formula 94 Part II: Using Functions in Your Formulas Chapter 4: Introducing Worksheet Functions 99 What Is a Function? 99 Simplify Formulas 100 Perform Otherwise Impossible Calculations 100 Speed Up Editing Tasks 100 Provide Decision-Making Capability 101 More about Functions 101 Function Argument Types 102 Names as Arguments 103 Full-Column or Full-Row as Arguments 103 Literal Values as Arguments 104 Expressions as Arguments 104 Other Functions as Arguments 105 Arrays as Arguments 105 Ways to Enter a Function into a Formula 106 Entering a Function Manually 106 Using the Insert Function Dialog Box to Enter a Function 107 More Tips for Entering Functions 109 Function Categories 111 Financial Functions 111 Date & Time Functions 111 Math & Trig Functions 112 Statistical Functions 112 Lookup and Reference Functions 112 Database Functions 112 Text Functions 112 Logical Functions 112 Information Functions 113 User-Defined Functions 113 Engineering Functions 113 Cube Functions 114 Other Function Categories 114

7 Table of Contents xiii Chapter 5: Manipulating Text 115 A Few Words about Text 115 How Many Characters in a Cell? 116 Numbers as Text 116 Text Functions 117 Determining Whether a Cell Contains Text 117 Working with Character Codes 118 Determining Whether Two Strings Are Identical 120 Joining Two or More Cells 121 Displaying Formatted Values as Text 122 Displaying Formatted Currency Values as Text 123 Counting Characters in a String 123 Repeating a Character or String 124 Creating a Text Histogram 124 Padding a Number 125 Removing Excess Spaces and Nonprinting Characters 126 Changing the Case of Text 127 Extracting Characters from a String 128 Replacing Text with Other Text 128 Finding and Searching within a String 129 Searching and Replacing within a String 130 Advanced Text Formulas 131 Counting Specific Characters in a Cell 131 Counting the Occurrences of a Substring in a Cell 131 Expressing a Number as an Ordinal 132 Determining a Column Letter for a Column Number 132 Extracting a Filename from a Path Specification 133 Extracting the First Word of a String 133 Extracting the Last Word of a String 134 Extracting All but the First Word of a String 134 Extracting First Names, Middle Names, and Last Names 135 Removing Titles from Names 137 Counting the Number of Words in a Cell 137 Custom VBA Text Functions 137 Chapter 6: Working with Dates and Times 139 How Excel Handles Dates and Times 140 Understanding Date Serial Numbers 140 Entering Dates 141 Understanding Time Serial Numbers 143 Entering Times 144 Formatting Dates and Times 145 Problems with Dates 147 Date-Related Functions 149 Displaying the Current Date 150 Displaying Any Date 151 Generating a Series of Dates 151 Converting a Non-Date String to a Date 153 Calculating the Number of Days between Two Dates 153

8 xiv Excel 2007 Formulas Calculating the Number of Work Days between Two Dates 154 Offsetting a Date Using Only Work Days 155 Calculating the Number of Years between Two Dates 156 Calculating a Person s Age 156 Determining the Day of the Year 158 Determining the Day of the Week 158 Determining the Date of the Most Recent Sunday 159 Determining the First Day of the Week after a Date 159 Determining the nth Occurrence of a Day of the Week in a Month 159 Counting the Occurrences of a Day of the Week 160 Expressing a Date as an Ordinal Number 161 Calculating Dates of Holidays 162 Determining the Last Day of a Month 165 Determining Whether a Year Is a Leap Year 165 Determining a Date s Quarter 165 Converting a Year to Roman Numerals 166 Time-Related Functions 166 Displaying the Current Time 166 Displaying Any Time 167 Summing Times That Exceed 24 Hours 168 Calculating the Difference between Two Times 170 Converting from Military Time 171 Converting Decimal Hours, Minutes, or Seconds to a Time 172 Adding Hours, Minutes, or Seconds to a Time 172 Converting between Time Zones 173 Rounding Time Values 174 Working with Non Time-of-Day Values 175 Chapter 7: Counting and Summing Techniques 177 Counting and Summing Worksheet Cells 178 Counting or Summing Records in Databases and Pivot Tables 180 Basic Counting Formulas 181 Counting the Total Number of Cells 182 Counting Blank Cells 182 Counting Nonblank Cells 183 Counting Numeric Cells 183 Counting Nontext Cells 183 Counting Text Cells 184 Counting Logical Values 184 Counting Error Values in a Range 184 Advanced Counting Formulas 185 Counting Cells by Using the COUNTIF Function 185 Counting Cells That Meet Multiple Criteria 186 Counting the Most Frequently Occurring Entry 190 Counting the Occurrences of Specific Text 191 Counting the Number of Unique Values 193 Creating a Frequency Distribution 194

9 Table of Contents xv Summing Formulas 201 Summing All Cells in a Range 201 Computing a Cumulative Sum 202 Summing the Top n Values 203 Conditional Sums Using a Single Criterion 204 Summing Only Negative Values 205 Summing Values Based on a Different Range 207 Summing Values Based on a Text Comparison 207 Summing Values Based on a Date Comparison 207 Conditional Sums Using Multiple Criteria 208 Using And Criteria 208 Using Or Criteria 210 Using And and Or Criteria 210 Chapter 8: Using Lookup Functions 211 What Is a Lookup Formula? 211 Functions Relevant to Lookups 212 Basic Lookup Formulas 213 The VLOOKUP Function 213 The HLOOKUP Function 215 The LOOKUP Function 216 Combining the MATCH and INDEX Functions 217 Specialized Lookup Formulas 218 Looking Up an Exact Value 219 Looking Up a Value to the Left 220 Performing a Case-Sensitive Lookup 221 Choosing among Multiple Lookup Tables 222 Determining Letter Grades for Test Scores 223 Calculating a Grade Point Average 224 Performing a Two-Way Lookup 225 Performing a Two-Column Lookup 227 Determining the Address of a Value within a Range 228 Looking Up a Value by Using the Closest Match 229 Looking Up a Value Using Linear Interpolation 230 Chapter 9: Tables and Worksheet Databases 233 Tables and Terminology 234 A Worksheet Database Example 234 A Table Example 234 Uses For Worksheet Databases and Tables 236 Working with Tables 237 Creating a Table 238 Changing the Look of a Table 239 Navigating and Selecting in a Table 241 Adding New Rows or Columns 241 Deleting Rows or Columns 242 Moving a Table 242 Setting Table Options 244 Removing Duplicate Rows from a Table 244

10 xvi Excel 2007 Formulas Sorting and Filtering a Table 245 Working with the Total Row 249 Using Formulas within a Table 253 Referencing Data in a Table 255 Converting a Table to a Worksheet Database 259 Using Advanced Filtering 259 Setting Up a Criteria Range 260 Applying an Adanced Filter 261 Clearing an Advanced Filter 262 Specifying Advanced Filter Criteria 263 Specifying a Single Criterion 263 Specifying Multiple Criteria 266 Specifying Computed Criteria 269 Using Database Functions 271 Inserting Subtotals 273 Chapter 10: Miscellaneous Calculations 277 Unit Conversions 277 Solving Right Triangles 279 Area, Surface, Circumference, and Volume Calculations 282 Calculating the Area and Perimeter of a Square 282 Calculating the Area and Perimeter of a Rectangle 282 Calculating the Area and Perimeter of a Circle 282 Calculating the Area of a Trapezoid 283 Calculating the Area of a Triangle 283 Calculating the Surface and Volume of a Sphere 283 Calculating the Surface and Volume of a Cube 283 Calculating the Surface and Volume of a Cone 284 Calculating the Volume of a Cylinder 284 Calculating the Volume of a Pyramid 284 Solving Simultaneous Equations 284 Rounding Numbers 286 Basic Rounding Formulas 287 Rounding to the Nearest Multiple 288 Rounding Currency Values 288 Working with Fractional Dollars 289 Using the INT and TRUNC Functions 290 Rounding to an Even or Odd Integer 290 Rounding to n Significant Digits 291 Part III: Financial Formulas Chapter 11: Borrowing and Investing Formulas 295 Financial Concepts 296 Time Value of Money 296 Cash In and Cash Out 296 Matching Time Periods 297 Timing of the First Payment 297

11 Table of Contents xvii The Basic Excel Financial Functions 298 Calculating Present Value 298 Calculating Future Value 302 Calculating Payments 305 Calculating Rates 306 Calculating Periods 309 Calculating the Interest and Principal Components 311 Using the IPMT and PPMT Functions 312 Using the CUMIPMT and CUMPRINC Functions 313 Converting Interest Rates 314 Methods of Quoting Interest Rates 314 Conversion Formulas 315 Limitations of Excel s Financial Functions 316 Deferred Start to a Series of Regular Payments 317 Valuing a Series of Variable Payments 317 Bond Calculations 318 Pricing Bonds 319 Calculating Yield 320 Chapter 12: Discounting and Depreciation Formulas 321 Using the NPV Function 322 Definition of NPV 322 NPV Function Examples 324 Using the NPV Function to Calculate Accumulated Amounts 330 Using the IRR Function 332 Rate of Return 333 Geometric Growth Rates 334 Checking Results 335 Multiple Rates of IRR and the MIRR Function 336 Multiple IRRs 336 Separating Flows 338 Using Balances Instead of Flows 339 Irregular Cash Flows 340 Net Present Value 340 Internal Rate of Return 341 Using the FVSCHEDULE Function 342 Calculating an Annual Return 342 Depreciation Calculations 343 Chapter 13: Financial Schedules 347 Creating Financial Schedules 347 Creating Amortization Schedules 348 A Simple Amortization Schedule 348 A Dynamic Amortization Schedule 351 Using Payment and Interest Tables 354 Credit Card Calculations 356 Summarizing Loan Options Using a Data Table 358 Creating a One-Way Data Table 358 Creating a Two-Way Data Table 360

12 xviii Excel 2007 Formulas Financial Statements and Ratios 362 Basic Financial Statements 362 Ratio Analysis 366 Creating Indices 369 Part IV: Array Formulas Chapter 14: Introducing Arrays 375 Introducing Array Formulas 375 A Multicell Array Formula 376 A Single-Cell Array Formula 377 Creating an Array Constant 378 Array Constant Elements 379 Understanding the Dimensions of an Array 380 One-Dimensional Horizontal Arrays 380 One-Dimensional Vertical Arrays 380 Two-Dimensional Arrays 381 Naming Array Constants 382 Working with Array Formulas 383 Entering an Array Formula 383 Selecting an Array Formula Range 384 Editing an Array Formula 384 Expanding or Contracting a Multicell Array Formula 386 Using Multicell Array Formulas 386 Creating an Array from Values in a Range 386 Creating an Array Constant from Values in a Range 386 Performing Operations on an Array 387 Using Functions with an Array 389 Transposing an Array 389 Generating an Array of Consecutive Integers 390 Using Single-Cell Array Formulas 391 Counting Characters in a Range 391 Summing the Three Smallest Values in a Range 392 Counting Text Cells in a Range 393 Eliminating Intermediate Formulas 395 Using an Array in Lieu of a Range Reference 396 Chapter 15: Performing Magic with Array Formulas 399 Working with Single-Cell Array Formulas 400 Summing a Range That Contains Errors 400 Counting the Number of Error Values in a Range 401 Summing Based on a Condition 402 Summing the n Largest Values in a Range 405 Computing an Average That Excludes Zeros 405 Determining Whether a Particular Value Appears in a Range 406 Counting the Number of Differences in Two Ranges 407 Returning the Location of the Maximum Value in a Range 408 Finding the Row of a Value s nth Occurrence in a Range 408

13 Table of Contents xix Returning the Longest Text in a Range 409 Determining Whether a Range Contains Valid Values 409 Summing the Digits of an Integer 410 Summing Rounded Values 411 Summing Every nth Value in a Range 412 Removing Non-Numeric Characters from a String 413 Determining the Closest Value in a Range 414 Returning the Last Value in a Column 414 Returning the Last Value in a Row 416 Ranking Data with an Array Formula 416 Creating a Dynamic Crosstab Table 417 Working with Multicell Array Formulas 418 Returning Only Positive Values from a Range 419 Returning Nonblank Cells from a Range 420 Reversing the Order of the Cells in a Range 420 Sorting a Range of Values Dynamically 421 Returning a List of Unique Items in a Range 422 Displaying a Calendar in a Range 423 Part V: Miscellaneous Formula Techniques Chapter 16: Intentional Circular References 429 What Are Circular References? 429 Correcting an Accidental Circular Reference 430 Understanding Indirect Circular References 431 Intentional Circular References 432 How Excel Determines Calculation and Iteration Settings 435 Circular Reference Examples 436 Generating Unique Random Integers 436 Solving a Recursive Equation 437 Solving Simultaneous Equations Using a Circular Reference 439 Animating a Chart Using Iteration 441 Potential Problems with Intentional Circular References 442 Chapter 17: Charting Techniques 443 Understanding the SERIES Formula 443 Using Names in a SERIES Formula 445 Unlinking a Chart Series from Its Data Range 447 Creating Links to Cells 448 Adding A Chart Title Link 448 Adding Axis Title Links 448 Adding Links to Data Labels 449 Adding Text Links 449 Chart Examples 449 Charting Progress Toward a Goal 450 Creating a Gauge Chart 451 Displaying Conditional Colors in a Column Chart 452 Creating a Comparative Histogram 453

14 xx Excel 2007 Formulas Creating a Gantt Chart 454 Creating a Box Plot 457 Plotting Every nth Data Point 459 Plotting the Last n Data Points 461 Selecting a Series from a Combo Box 462 Plotting Mathematical Functions 463 Plotting a Circle 468 Creating a Clock Chart 469 Creating Awesome Designs 473 Working with Trendlines 474 Linear Trendlines 475 Working with Nonlinear Trendlines 478 Chapter 18: Pivot Tables 485 About Pivot Tables 485 A Pivot Table Example 486 Data Appropriate for a Pivot Table 488 Creating a Pivot Table 491 Specifying the Data 491 Specifying the Location for the Pivot Table 492 Laying Out the Pivot Table 493 Formatting the Pivot Table 493 Modifying the Pivot Table 496 More Pivot Table Examples 498 Question Question Question Question Question Question Grouping Pivot Table Items 504 A Manual Grouping Example 504 Viewing Grouped Data 505 Automatic Grouping Examples 505 Creating a Frequency Distribution 510 Creating a Calculated Field or Calculated Item 513 Creating a Calculated Field 514 Inserting a Calculated Item 516 Referencing Cells within a Pivot Table 519 Another Pivot Table Example 521 Producing a Report with a Pivot Table 524 Chapter 19: Conditional Formatting and Data Validation 527 Conditional Formatting 527 Specifying Conditional Formatting 528 Conditional Formats That Use Graphics 532 Working with Conditional Formats 542 Creating Formula-Based Rules 544

15 Table of Contents xxi Data Validation 554 Specifying Validation Criteria 555 Types of Validation Criteria You Can Apply 556 Creating a Drop-Down List 558 Using Formulas for Data Validation Rules 559 Chapter 20: Creating Megaformulas 563 What Is a Megaformula? 563 Creating a Megaformula: A Simple Example 564 Megaformula Examples 566 Using a Megaformula to Remove Middle Names 567 Using a Megaformula to Return a String s Last Space Character Position 570 Using a Megaformula to Determine the Validity of a Credit Card Number 574 Generating Random Names 578 The Pros and Cons of Megaformulas 580 Chapter 21: Tools and Methods for Debugging Formulas 581 Formula Debugging? 581 Formula Problems and Solutions 582 Mismatched Parentheses 583 Cells Are Filled with Hash Marks 584 Blank Cells Are Not Blank 584 Extra Space Characters 585 Formulas Returning an Error 585 Absolute/Relative Reference Problems 589 Operator Precedence Problems 590 Formulas Are Not Calculated 591 Actual versus Displayed Values 591 Floating-Point Number Errors 592 Phantom Link Errors 593 Logical Value Errors 594 Circular Reference Errors 595 Excel s Auditing Tools 595 Identifying Cells of a Particular Type 596 Viewing Formulas 597 Tracing Cell Relationships 599 Tracing Error Values 600 Fixing Circular Reference Errors 601 Using Background Error Checking 601 Using Excel s Formula Evaluator 603 Part VI: Developing Custom Worksheet Functions Chapter 22: Introducing VBA 607 About VBA 607 Displaying the Developer Tab 608 About Macro Security 609 Saving Workbooks That Contain Macros 610

16 xxii Excel 2007 Formulas Introducing the Visual Basic Editor 611 Activating the VB Editor 611 The VB Editor Components 611 Using the Project Window 613 Using Code Windows 616 Entering VBA Code 618 Saving Your Project 621 Chapter 23: Function Procedure Basics 623 Why Create Custom Functions? 624 An Introductory VBA Function Example 624 About Function Procedures 626 Declaring a Function 626 Choosing a Name for Your Function 627 Using Functions in Formulas 628 Using Function Arguments 629 Using the Insert Function Dialog Box 630 Adding a Function Description 630 Specifying a Function Category 631 Testing and Debugging Your Functions 633 Using the VBA MsgBox Statement 634 Using Debug.Print Statements in Your Code 636 Calling the Function from a Sub Procedure 637 Setting a Breakpoint in the Function 640 Creating Add-Ins 641 Chapter 24: VBA Programming Concepts 645 An Introductory Example Function Procedure 646 Using Comments in Your Code 648 Using Variables, Data Types, and Constants 649 Defining Data Types 649 Declaring Variables 650 Using Constants 652 Using Strings 653 Using Dates 654 Using Assignment Expressions 654 Using Arrays 656 Declaring an Array 656 Declaring Multidimensional Arrays 657 Using Built-In VBA Functions 657 Controlling Execution 659 The If-Then Construct 659 The Select Case Construct 661 Looping Blocks of Instructions 662 The On Error Statement 667 Using Ranges 668 The For Each-Next Construct 669 Referencing a Range 669 Some Useful Properties of Ranges 672

17 Table of Contents xxiii The Set Keyword 676 The Intersect Function 676 The Union Function 677 The UsedRange Property 677 Chapter 25: VBA Custom Function Examples 679 Simple Functions 680 Determining a Cell s Data Type 685 A Multifunctional Function 687 Generating Random Numbers 689 Calculating Sales Commissions 692 Text Manipulation Functions 695 Counting Functions 701 Date Functions 703 Returning the Last Nonempty Cell in a Column or Row 706 Multisheet Functions 708 Advanced Function Techniques 710 Part VII: Appendixes Appendix A: Excel Function Reference 727 Appendix B: Using Custom Number Formats 745 About Number Formatting 745 Creating a Custom Number Format 749 Custom Number Format Examples 754 Appendix C: Additional Excel Resources 767 The Excel Help System 767 Microsoft Technical Support 768 Internet Newsgroups 769 Web Sites 771 Appendix D: What s on the CD-ROM 773 System Requirements 773 Using the CD 774 Files and Software on the CD 774 Troubleshooting 782 Index 783