• Created By:
Ashley Donohue and Gerald Hosler

## Rules to Writing Numbers  April 20th, 2012

Rule 1: Spell out single-digit whole numbers.  Use numerals for numbers greater than nine.
Ex] I want five copies. OR I want 10 copies.

Rule 2: Be consistent within a category.  If you choose to spell out numbers because one of the numbers is  a single digit, spell out all numbers in that category.
Ex]  My ten cats fought with their two cats.

Rule 3: Always spell out simple fractions and use hyphens with them.
Ex]  One-third of the class likes apple pie.

Rule 4: A mixed fraction can be expressed in figures unless it is the first word of a sentence.
Ex]  We expect a 5 1/2 percent wage increase.  OR  Five and one-half percent was the maximum allowable interest.

Rule 5: The simplest way to express large numbers is best.  Round numbers are usually spelled out.
Ex]  You can earn from one million to five million dollars.  OR  You can earn from \$5 hundred to \$5 million.

Rule 6: Write decimals in figures.  Put a zero in front of a decimal unless the decimal begins with a zero.
Ex]  The plant grew 0.79 of a foot in one year.  OR  The plant only grew .07.

Rule 7: With numbers that have decimal points, use a comma only when the number has five or more digits before the decimal point.  Use the word and where the decimal point appears in the figure format.
Ex]  \$15,768.13: Fifteen thousand, seven hundred sixty-eight dollars and thirteen cents

Rule 8: Following examples apply to dates:
Ex]  The meeting is scheduled for June 30.
The meeting is scheduled for the 30th of June.

Rule 9: When expressing decades, you may spell them out and lowercase them.
Ex]  During the eighties and nineties, the U.S. economy grew.

Rule 10: If you wish to express decades using incomplete numerals, put an apostrophe before the incomplete numeral but not between the year.
Ex]  During the ’80s and ’90s, the U.S. economy grew.

Rule 11: You may also express decades in complete numerals.  Again, don’t use an apostrophe between the year.
Ex]  During the 1980s and 1990s, the U.S. economy grew.

Rule 12: Spell out the time of day in text even with half and quarter hours.  With o’clock, the number is always spelled out.
Ex]  She gets up at four thirty before the baby wakes up.  OR  The baby wakes up at five o’clock in the morning.

Rule 13: Use numerals with the time of day when exact times are being emphasized or when using A.M. or P.M.
Ex]  Please arrive by 6:22 A.M.

Rule 14: Use noon and midnight rather than 12:00 P.M. and 12:00 A.M.

Rule 15: Hyphenate all compound numbers from twenty-one through ninety-nine.
Ex]  Twenty-three of them were hospitalized.

Rule 16: Write out a number if it begins a sentence.
Ex] Twenty-nine people won an award for helping their communities.

Rule 17: Addresses must be written in numerical form.
Ex] 2260 NW Century Drive  Corvallis, OR 97330