What is the meaning of Percentage_rate?

A measure to show a change or relationship between two numbers as a fraction of 100, over a certain time.

A coefficient, expressed as a fraction of 100, of the quotient of two numbers over a specified period of time, where the denominator has the same units as the numerator but is adjusted by a unit of time. This measure indicates the proportion of a part in relation to a whole and is commonly used to describe rates of interest, growth, or change in financial and economic contexts, expressed in percentage points.

Source: wiktionary.org