Percentual

Percentual is a term used to denote a portion of a whole expressed as a percentage. In mathematics, a percent means a quantity per hundred and is written with the symbol %. The word is used in various languages to refer to the same concept, with English speakers typically using "percentage" or "percent." The relationship between percent, decimal, and fraction is: percent = decimal × 100; decimal = percent / 100; fraction = percent / 100.

To compute a percentage of a quantity, multiply the quantity by its decimal equivalent or apply (part/whole) × 100. For example, 25% of 200 equals 50. Percentages are used to describe changes (percentage change), shares of a total, probabilities, rates, and other proportions in fields such as finance, statistics, economics, and demographics. Percentage change is calculated as ((new value − old value) / old value) × 100, indicating the magnitude of change in percent.

Common pitfalls include confusing percentage points with percentages, misplacing the percent sign, or mixing percentages with raw numbers without proper conversion. Percentiles, by contrast, are a related but distinct concept used to rank data, indicating the value below which a given percentage of observations fall.

Historically, the concept developed during medieval mathematics and gained prominence with decimal notation and commercial accounting. In data presentation, percentages should be stated with a clear base (for example, “of total sales” or “relative to population size”) to ensure proper interpretation.