Retentioarvo

Retentioarvo is a term used to describe the portion or value of something that remains after a defined process or condition. The word combines Finnish roots related to retention and value and is used across several disciplines to express how much of an initial quantity is still present when the process has ended or a measurement is taken.

Definition and measurement

In general, retentioarvo is the retained amount divided by the initial amount, often shown as a percentage. What counts as “retained” depends on the context: it can be mass, concentration, number of items, or other quantitative measures. The concept is inherently comparative and time- or condition-specific, since retention can change with duration, environmental factors, or process parameters.

Applications and contexts

- In filtration or adsorption, retentioarvo describes the fraction of a solute that remains bound or trapped by a material.

- In pharmacology or drug delivery, it can refer to the amount of a substance remaining in a matrix or release system over time.

- In data and user analytics, retentioarvo may denote the proportion of users who continue to engage after a defined period.

- In environmental engineering or hydrology, it can describe the amount of water or contaminant retained by soils or substrates under certain conditions.

Calculation and interpretation

Calculations typically rely on a mass balance or measurement of the initial and retained quantities. Reported values should specify the time point, the reference state, and the exact definition of “retained” to avoid ambiguity. Limitations arise from changing conditions, measurement error, and the dependence on how retention is defined for the particular study.

See also: retention rate, adsorption capacity, recovery, mass balance.