In mathematics, a **percentage** is a number or ratio as a fraction of 100. It is often denoted using the percent sign, “%”, or the abbreviation “pct.”

For example, 45% (read as “forty-five percent”) is equal to 45/100, or 0.45. A related system which expresses a number as a fraction of 1000 uses the terms "per mil" and "millage". Percentages are used to express how large/small one quantity is, relative to another quantity. The first quantity usually represents a part of, or a change in, the second quantity, which should be greater than zero. For example, an increase of $ 0.15 on a price of $ 2.50 is an increase by a fraction of 0.15/2.50 = 0.06. Expressed as a percentage, this is therefore a 6% increase.

Although percentages are usually used to express numbers between zero and one, any ratio can be expressed as a percentage. For instance, 111% is 1.11 and −0.35% is −0.0035. Although this is technically inaccurate as per the definition of percent, an alternative wording in terms of a change in an observed value is “an increase/decrease by a factor of...””

Read more about Percentage: History, Calculations, Percentage Increase and Decrease, Word and Symbol, Related Units, Other Uses, Practical Applications

### Famous quotes containing the word percentage:

“If marriages were made by putting all the men’s names into one sack and the women’s names into another, and having them taken out by a blindfolded child like lottery numbers, there would be just as high a *percentage* of happy marriages as we have here in England.... If you can tell me of any trustworthy method of selecting a wife, I shall be happy to make use of it.”

—George Bernard Shaw (1856–1950)

“Actually, if my business was legitimate, I would deduct a substantial *percentage* for depreciation of my body.

Contemplative and bookish men must of necessitie be more quarrelsome than others, because they contend not about matter of fact, nor can determine their controversies by any certain witnesses, nor judges. But as long as they goe towards peace, that is Truth, it is no matter which way.”

—John Donne (c. 1572–1631)

“There is a potential 4-6 *percentage* point net gain for the President [George Bush] by replacing Dan Quayle on the ticket with someone of neutral stature.”

—Mary Matalin, U.S. Republican political advisor, author, and James Carville b. 1946, U.S. Democratic political advisor, author. All’s Fair: Love, War, and Running for President, p. 205, Random House (1994)