Date.StartOfYear

Date

Returns the first day of the year for a given date.

Syntax

Date.StartOfYear(dateTime as any) as any

Parameters

Name	Type	Required	Description
`dateTime`	`any`	Yes	The date, datetime, or datetimezone value to find the start of the year for.

Return Value

any — The first day of the year containing the input date.

Remarks

Date.StartOfYear returns January 1 of the year for the given date, datetime, or datetimezone value. The return type matches the input type. If the input is null, the function returns null.

Examples

Example 1: Find the start of year for each hire date

Table.AddColumn(
    Table.SelectColumns(
        Table.FirstN(Employees, 4),
        {"FullName", "HireDate"}
    ),
    "YearStart", each Date.StartOfYear([HireDate]), type date
)

Result

	FullName	HireDate	YearStart
1	John Smith	3/15/2021	1/1/2021
2	Sara Johnson	7/1/2019	1/1/2019
3	Mike Davis	1/10/2022	1/1/2022
4	Emily Chen	6/20/2023	1/1/2023

Example 2: Start of year from a scalar value

#table(
    type table [Date = date, StartOfYear = date],
    {{#date(2024, 4, 15), Date.StartOfYear(#date(2024, 4, 15))}}
)