A Decile is a quantitative method of splitting up a set of ranked data into 10 equally large subsections. This type of data ranking is performed as part of many academic and statistical studies in the finance and economics fields. The first step in creating a decile ranking is to order the data from smallest to largest. Once the data has been ordered, it is then divided into ten equal parts, with each part representing one tenth (or 1/10) of the total number of items in the set. The second decimal place is used to determine which subsection each item falls into (i.e., if there are 5 items in the set and they are ranked from 1-5, then items 1-0.9 would be placed in Decile #1, while item 0.10 would be placed in Decile #2).Although there are many different applications for deciles, they are most commonly used within finance and economics as a way to measure certain aspects of market performance or economic trends. In particular, deciles can be used to help identify where specific points fall within various distributions (such as bell curves), or to track how different groups (such as income levels) perform over time relative to each other. They can also be helpful for detecting outliers - that is, unusually high or low values that don't fit within the rest of the dataset. Overall, deciles offer a simple yet powerful way to analyze large amounts of data quickly and easily.
