This project does not predict the future. It uses official demographic life tables to approximate how many more times you might see someone important in person, if current conditions persist. It's a statistical mirror, not a sentence.
Expected in-person visits remaining between two people.
Based on the probability that both are alive in each future year, multiplied by the visit frequency you currently maintain.
Primary data source
What it provides:
Organization: United Nations, Population Division
Update: 2024 (most recent revision)
View official sourceIf you currently see the person 12 times a year, we assume that will continue. In reality it may increase or decrease.
Life tables represent the average experience of a population, they don't consider individual health.
We don't know specific illnesses, lifestyle habits, or particular conditions.
Socioemotional Selectivity Theory (Carstensen, 1999, 2021) demonstrates that when people perceive their future time as limited, they prioritize close relationships and emotional goals over exploration or information accumulation.
People tend to underestimate how finite their time with others is. A concrete number helps make more conscious decisions about priorities.
Scientific reference:
Carstensen, L. L. (2021). Socioemotional Selectivity Theory: The Role of Perceived Endings in Human Motivation. The Gerontologist, 61(8), 1188–1196.
Read article (open access)Data from the American Time Use Survey (Bureau of Labor Statistics, USA) and analysis from Our World in Data show that:
This means that most of the time has already been spent, even when both are still alive.
Why don't we show this data? We decided not to include the "time already spent" percentage in the calculator because the goal of this tool is to motivate action toward the future, not generate guilt about the past. Showing that "you've already spent 85% of your time with your mother" can provoke hopelessness or resignation, contradicting the tool's purpose. Additionally, this data comes from American surveys that may not reflect the reality of other cultures where family coexistence patterns differ.
The probability that a person of age a survives an additional t years is calculated using the life table survival function:
This is the standard conditional survival formula (Preston et al., Ch. 3).
We determine the calculation horizon up to the maximum age in life tables (100 years), which allows us to capture all possible scenarios:
Where a₁ is your age and a₂ is the other person's age. This ensures we don't underestimate visits from people who live beyond their life expectancy.
Assuming independence between the deaths of both persons, the probability that both are alive in year t is:
This independence assumption is standard in formal demography.
The expected number of visits is the weighted sum of frequency by joint survival probability:
Each year contributes proportionally to the probability that both are still alive.
We run 10,000 simulations to obtain statistically valid confidence intervals. In each simulation, we sample the death year for each person using the qx probabilities:
This provides real confidence intervals based on the empirical distribution of possible outcomes.
Methodological reference: Preston, S. H., Heuveline, P., & Guillot, M. (2001). Demography: Measuring and Modeling Population Processes. Blackwell Publishers. Chapters 2-3.