Calculate years since a date — years

Computes the number of years (as a decimal) between a date and a reference date. Useful for calculating time since last gift, years of giving, or other duration metrics.

Usage

years_since(date, as_of = Sys.Date(), digits = 1L)

Arguments

date: Date vector (or coercible via as.Date()).
as_of: Reference date. Default is today.
digits: Number of decimal places to round to. Default 1. Use NULL for no rounding.

Value

Numeric vector of years. Negative values indicate future dates. Returns NA for NA inputs.

Examples

years_since(as.Date("2020-06-15"))
#> [1] 5.7

years_since(as.Date("2020-06-15"), as_of = as.Date("2024-06-15"))
#> [1] 4
#> 4.0

# Vectorized
dates <- as.Date(c("2020-01-01", "2022-06-15", "2023-09-01"))
years_since(dates, as_of = as.Date("2024-06-15"))
#> [1] 4.5 2.0 0.8