Term · Portfolio & Execution
Days to Build Position
In briefDays to build estimates how many trading days it takes to build a target position while trading only a reasonable share of daily volume. For thinly traded small-caps the metric guards against oversized positions and a self-inflicted price jump on entry.
Definition
An estimate of how many trading days are needed to build a target position without trading too high a share of the daily volume.
How it is calculated
Formula. Days to Build = target position value ÷ (ADTV × permitted participation rate).
Why it matters for small caps
For narrow small-caps, the metric protects against unrealistic position sizes and a self-caused price jump on entry.
Common misreadings
- It is often confused with "you could theoretically buy"; decisive is market-friendly execution.
In the process
Frequently asked
What does days to build position measure?
It indicates how long building a position is likely to take. The basis is a limited participation in the daily trading volume.
How do you calculate days to build?
You divide the target position value by the product of average daily turnover and permitted participation rate. This yields the estimated build-up duration.
Why is theoretical buyability not enough?
That you could buy says nothing about market-friendly execution. Decisive is whether the position can be built without a price jump.
Related terms
Sources
Primary
CFA Institute – Trade Strategy and Execution
https://www.cfainstitute.org/insights/professional-learning/refresher-readings/2026/trade-strategy-execution
https://www.cfainstitute.org/insights/professional-learning/refresher-readings/2026/trade-strategy-execution
Methodology
EUR-Lex – MiFID II, Richtlinie 2014/65/EU
https://eur-lex.europa.eu/eli/dir/2014/65/oj
https://eur-lex.europa.eu/eli/dir/2014/65/oj
Education only, not investment advice. Ranges and thresholds are didactic orientation values, not an official standard.