Page 18 - Excel Data Analysis

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EXCEL DATA ANALYSIS

EXCEL DATA TYPES

n Excel, a data type refers to the type of value stored in The default data type that Excel assigns to a cell determines
a cell. When you input data, Excel automatically parses it the type of data analysis you can apply to it. For example,
I and determines its data type. Excel recognizes three most data analysis tools require numeric values; if you try to
different data types: text, numeric, and formula. use a text value, the tools return error messages.

TEXT

Text data types contain letters for use as text or labels Excel determines that a cell contains text, it left-justifies
within a worksheet. You typically place labels in a the entire contents of the cell.
worksheet to identify columns and rows that contain
numeric values. However, not all values that contain a You cannot perform any mathematical operations on a
letter are text. For example, although 1.45E+05 contains number as long as the cell also contains text. For this
a letter, Excel recognizes it as a number expressed in reason, you may want to consider separating text and
scientific notation. numeric values into two separate cells. If you want Excel
to treat a numeric value, such as Zip Code or Social
You can use any combination of letters and numbers in Security Number, as text, you place an apostrophe (')
a cell as long as the total number of characters in the before the numeric value in the cell.
cell does not exceed 32,000 characters. By default, when

NUMERIC

A numeric value is any number, percentage, currency, they are considered numeric values. You can customize
time, or date value. By default, Excel formats all numeric the look of numeric values using the Number tab on the
values by right-justifying them in the cell. Because Excel Format Cells dialog box.
has a specific method for storing date and time values,

Number Fractions
Excel allows nearly any number you can possibly type If you type a fraction in a cell without preceding it with
in a cell within the range 2.250748585072E-308 to a number, Excel automatically converts it to a date.
1.797693486231E308. You can input numbers in a To avoid this conversion, place an apostrophe (') or zero
wide variety of formats or use the six different built-in (0) in front of it. No matter what number precedes a
number formats to customize how a number displays in fraction, you must leave a space between the number
a cell.
and the fraction.
Numeric Characters
Number Precision
You can use any of the following characters to express a Excel only guarantees precision up to 15 digits and
numeric value: 0 1 2 3 4 5 6 7 8 9 + , - ( ) / $ % . E e. The converts any digits beyond 15 to zeros without rounding
placement of the characters within the number is values up to the nearest place. For example, Excel converts
important. For example, the letters E and e allow you to both 35,555,545,365,875,988 and 35,555,545,365,875,922 to
express large numbers, such as 1,256,000,000,000 in a 35,555,545,875,900. Obviously this limitation makes storing
format that is easier to display, 1.256E+12, called large numbers, such as a 16-digit credit card number, in
scientific notation. If you use an E in any other location, their entirety difficult. To avoid truncating credit card
such as preceding a number (E54), Excel treats the cell numbers, you can format cells as text or create a special
contents as text.
number format. See the section "Create a Custom
Number Format" for more information.

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