percentage-point
UK[pəˈsentɪdʒ pɔɪnt]US[pərˈsentɪdʒ pɔɪnt]
n
A unit of measure equal to one hundredth of a percentage point, used especially in describing changes in interest rates or other financial figures.
n
The difference between two percentages.
Etymology
The term is a modern financial and statistical compound. 'Percentage' entered English in the late 16th century from the commercial Italian phrase per cento, itself derived from Latin per centum ("by the hundred"), reflecting a calculation out of one hundred. 'Point' has a long history, from Latin punctum ("a puncture, a small spot"), which evolved to signify a precise position or a unit of measurement. The fusion into "percentage point" in the 20th century created a precise unit for expressing arithmetic differences between percentages, a crucial concept for avoiding ambiguity in economics and data analysis, as a change from 10% to 12% is a rise of two percentage points, not a 2% rise.
Analysis
This is a compound noun formed from two simplex words: 'percentage' (from Italian per cento, via Latin per centum meaning "by the hundred") and 'point' (from Latin punctum meaning "a prick, a small mark"). In this compound, 'percentage' functions as a noun modifier and 'point' as the head noun.
Examples
The central bank raised the key interest rate by a quarter of a percentage point.
The candidate's lead in the polls widened by three percentage points after the debate.
Analysts noted a half percentage point difference between the two inflation measures.