Features of spread sheet A spreadsheet has three main components namely; worksheets, database, and charts.

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1 Topic 7: Electronic Spreadsheet An electronic spreadsheet is an application software used to calculate, organized and analyze numerical data. It consists of rows and column similar to ones of the manual spreadsheet. Examples of electronic spread sheet are Microsoft Excel, Open Office Calc, Lotus and Corel Quattro Pro. Advantages of electronic spreadsheets 1. Utilizes the powerful aspects of the computer like speed, accuracy and efficiency to enable the user quickly accomplish his/her tasks. 2. Offers a large virtual sheet for data entry and manipulation. 3. Utilizes the large storage space on computer storage devices to save and retrieve documents. 4. Enables the user to produce neat work. 5. Have a better document formatting capabilities. 6. Have inbuilt formulae called functions that enable the user to quickly manipulate mathematical data. 7. Automatically adjust the result of a formula if the values in a worksheet are changed. This is called the automatic recalculation features. Features of spread sheet A spreadsheet has three main components namely; worksheets, database, and charts. Worksheet A worksheet is the work area made up of rows and columns where data is entered. Each row is labelled using a number while each column is labelled with a letter as shown below. Cell is the intersection between a row and a column. Each cell is referenced using the column header label followed by the row label. In the work sheet the active cell is A1. Database

2 A database is a collection of related data items organized so as to provide a consistent and controlled access to items. In spreadsheets, a worksheet list may contain related data, organized into rows that can be manipulated using database functions that enable the user perform functions such as sorting, filtering, validation subtotaling, pivot tables and consolidation. Graphs A graph is a pictorial representation of the base data on a worksheet. Most spreadsheet refers to graphs as charts. A chart enables the user to present complex data elements from a worksheet in a simple easy to understand format. Examples of charts are pie charts, line charts and bar charts and bar charts. Application areas of spreadsheet Statistical analysis

3 Spreadsheets provide a set of data analysis tools that can be used to perform simple analysis such as computing mean, mode, and standard deviation as well as complex statistical analysis. However, some of these statistical functions are quite complex and requires a deeper understanding of knowledge in statistics. Accounting Accountants find electronic spreadsheets useful tools for analyzing financial transactions such as computing totals, consolidating financial records, as well as predicting future business trends. Most spreadsheet packages have inbuilt functions used to analyze financial data. Mathematical and scientific Spreadsheets are used to solve mathematical and scientific problems such as arithmetic and trigonometric. Forecasting A feature known as What if analysis, is used to make future predictions. Forecasting is an import function used for predicting economic trends budgeting, stock portfolio analysis, cost analysis and cash flow analysis. Working with spreadsheet Microsoft excel has a number of versions this include Excel 97, Excel 200, excel XP, excel 2003, Excel 2007, Excel 2010 and Excel Starting Microsoft Excel Click on start menu and point to programs/all programs. 2. Point to Microsoft office. 3. Click Microsoft Office Excel 2007 Main features of Microsoft office excel Formula bar Formula bar is where a cell entry or formula is displayed before being entered into the selected cell. Worksheets A worksheet is the work area made up of rows and column where data is entered. Cells A cell is an intersection between a row and a column. A column is a vertical arrangement of cells labelled A,B,C while a row is the horizontal arrangement labeled 1,2,3 Active cell pointer A cell pointer indicates the current active cell. The active cell pointer is highlighted with a dark, green outline.

4 Cell address The cell address is the combination of a column header and a row header that indicate the location of specific cell. For example G4 is the active cell address. Worksheet tabs Worksheet tabs are located at the bottom of a spreadsheet. They show the number of worksheets in the workbook. A workbook is a spreadsheet file that consist of one or more related worksheets. One worksheet may consist of one or several pages. Entering data into a worksheet As you type an entry, it is displayed in the formula bar. To place the content into the active cell press Enter key, an arrow key or click into another cell. Cell data entries Entries into a worksheet can be classified into four categories namely: 1. Labels 2. Values 3. Formulae 4. Functions Labels Any text or alphanumeric characters entered in cell are views as labels by the spreadsheet program. Labels are used as row or column headings usually describe the contents of the row or column. Values These are numbers that can be manipulated mathematically. They may include currency, date, numbers (0-9), Special symbols or text that can be manipulated mathematically by the spreadsheet. Formulae Formulae are mathematical expression that creates a relationship between cells to return a new value. In Excel, a formula must start with an equal sign. For example, the formula =A1+B1 adds the contents of B3 and D4 and returns the sum value in the current cell. Excel formulae use cell addresses and arithmetical operators; addition (+), subtraction (-), multiplication (*) and division (/). Using cell address, called referencing, enables Microsoft excel to keep calculations accurate and automatically recalculates results of a formula in case the value in a referenced cell is changed. This is called automatic recalculation. Functions

5 There are inbuilt predefined formulae that the user can quickly use instead of having to create a new one each time a calculation has to be carried out. Microsoft excel has many of these formulae that covers the most common types of calculations performed by spreadsheets. For example to add contents of cell B3+D3 type =Sum (B3:E3) Saving a workbook To save a workbook: 1. Click File menu option, then select save as command. Alternatively, click the save command on the standard toolbar. The Save as dialog box is displayed. 2. Select the location in which your workbook will be saved in the save in box, then type a unique name for the workbook is selected under the save as type box. 3. Click the save button to save. Opening a workbook 1. On the file menu or standard toolbar, click Open. 2. Click the look in drop down list arrow and select the drive or folder where the workbook was saved. 3. Double click the workbook icon that you want and the worksheet. Closing a workbook and exit On the File menu click close. This closes the current workbook but does not close the application. To exit from Excel, on the file menu, click Exit or press Alt +F4. Formulae and Functions Formula is a mathematical expression used to solve mathematical problems while a function is an inbuilt formula used to perform calculations. In excel formula or function must start with an equal sign (=). Arithmetic operators Arithmetic operators mostly follow the rule similar to mathematical concept of BODMAS. This means multiplication and division are evaluated form left to right while addition and subtraction are evaluated last. Summary of operators used to create formulae Symbol Description Example / Division =A6/B6 * Multiplication =A6*B6 + Addition =A6+B6 - Subtraction =B6 -A6 Relational operators

6 A relational operators returns either true or false depending on the magnitude of the value being evaluated. Summary of a rational operator Symbol Description Example = Equal to =A2/B2 > Greater than =A2>B2 < Less than =A2<B2 <> Not equal to =A2<>B2 <= Less than or equal to =A2<=B2 >= Greater than or equal to =A2>=B2 Operators Precedence If several operators are used in a single formula, Microsoft Excel performs the operations in the order shown in table below. A formula with operators that have same precedence i.e. if a formula contains both multiplication and division, operators are evaluated from left to right. Enclosing part of the formula to be calculated in parentheses or brackets makes that part to be calculated first. Cell referencing Operator Name Precedence - Negation as in -1 1 % Percent 2 ^ Exponentiation 3 *and/ Multiplication and division 4 +and- Addition and subtraction 5 =,<>,>,<,<=,>= Rational 6 There are three types of cell referencing used when creating formulae and manipulating cell(s) content. Relative referencing When you copy a formula that contains cell references, say A3, the references adjust to their new location. For example if C1 containing a formula = A1+B1 is copied to C2, the reference changes to A2+B2. Absolute referencing The reference is made to a specific address and does not change even if the formula is copied to another cell. In Excel an absolute cell reference is made by placing a dollar sign before the reference e.g $A$2. For Example if the result in C1 is 170, if absolute reference is used, 170 will be copied to C2.

7 Mixed cell referencing This is a combination of relative and absolute references, e.g $A3 or A$3. In the first case the column reference is absolute while the row is relative, in the second case the column reference is relative while the row reference is absolute. Using in-built functions A function must start with an(=) sign followed by the function name and arguments. Arguments are numeric, logical values or text enclosed in parenthesis. For example, in =SUM(A3:F3), SUM is the function that adds the range A3 to F3 which is the argument. In Microsoft Excel, functions are categorized according to the nature of problems they work on. We shall look at the following categories of in-built functions: Mathematical Statistical Logical Date and time The use of a function from any category: 1. On the Formulas menu, click insert function. Alternatively click the fx button or drop down of the AutoSum. And click more Functions. 2. In the function dialog box is displayed. 3. In the function list box, select a function. 4. Specify the function argument the click OK.

8 Mathematical functions Some commonly used mathematical functions are: SUM ( ) Adds all the value in the selected range of cells. For example if A3, B3 and C3 contains 20,50, and 80 respectively, =SUM(A3:C3) Returns 150. ROUND ( ) rounds a number to a specified number of decimal places. Zero rounds off the number to the nearest integer. For example, =ROUND(79.969,2) returns while =ROUND(79.969,0) returns 50. SUMIF ( ) Conditionally adds the specified cells according to the set criteria. =SUMIF(A3:A10, >=500 ) returns a value is greater than or equal to 500. PRODUCT ( ) Multiplies all the values in the argument. For example, =PRODUCT (40,3,2) returns 240. Statistical functions Some commonly used statistical functions are: AVERAGE ( ) Returns the arithmetic mean of its arguments. For example, =AVERAGE(A2:D2). COUNT ( ) Counts the number of cell