I would like to create the start and end date of a calendar year from a calendar year variable (here 1991 to 2001), and found a solution:
library(lubridate)
library(dplyr)
df <- tibble(calendar_year = seq(1991, 2001, 1))
df |>
mutate(
calendar_year_start_date = ymd("1991-01-01") +
years(calendar_year - 1991),
calendar_year_end_date = ymd("1991-12-31") +
years(calendar_year - 1991 )
)
Result:
# A tibble: 11 × 3
calendar_year calendar_year_start_date calendar_year_end_date
<dbl> <date> <date>
1 1991 1991-01-01 1991-12-31
2 1992 1992-01-01 1992-12-31
3 1993 1993-01-01 1993-12-31
4 1994 1994-01-01 1994-12-31
5 1995 1995-01-01 1995-12-31
6 1996 1996-01-01 1996-12-31
7 1997 1997-01-01 1997-12-31
8 1998 1998-01-01 1998-12-31
9 1999 1999-01-01 1999-12-31
10 2000 2000-01-01 2000-12-31
11 2001 2001-01-01 2001-12-31
it works; but I am looking for a more elegant solution. Thank you for any hint!
Another way, using make_date:
df |> mutate(start_date = make_date(calendar_year, 1, 1),
end_date = make_date(calendar_year, 12, 31))
Or
df |> mutate(start_date = ymd(calendar_year, truncated = 2), # credit to Uwe: https://stackoverflow.com/a/48489338/4145280
end_date = ceiling_date(start_date, "year") - days(1))
Output:
# A tibble: 11 × 3
calendar_year start_date end_date
<dbl> <date> <date>
1 1991 1991-01-01 1991-12-31
2 1992 1992-01-01 1992-12-31
3 1993 1993-01-01 1993-12-31
4 1994 1994-01-01 1994-12-31
5 1995 1995-01-01 1995-12-31
6 1996 1996-01-01 1996-12-31
7 1997 1997-01-01 1997-12-31
8 1998 1998-01-01 1998-12-31
9 1999 1999-01-01 1999-12-31
10 2000 2000-01-01 2000-12-31
11 2001 2001-01-01 2001-12-31