decile
noun [ C ]
uk/ˈdesaɪl/ us/ˈdesəl/in statistics, one of ten equal parts that a set of people or things is divided into, when you are comparing a particular feature relating to them:
a top-decile-performing UK fund
Households from the poorest two income deciles are likely to be housed in rented accommodation.
Compare
median
percentile
quartile