What is the STARTOFYEAR Function?
The STARTOFYEAR function is part of the Date and Time functions in Power BI. This function takes a date as input and returns the first day of the year in which the input date falls. For example, if the input date is “4/15/2021”, the STARTOFYEAR function would return “1/1/2021”.
The syntax of the STARTOFYEAR function is as follows:
Where `❰date❱` is the date value for which you want to find the first day of the year.
How to Use the STARTOFYEAR Function
The STARTOFYEAR function can be used in a variety of ways to analyze data. Here are some examples of how you can use this function in your Power BI reports:
Example 1: Calculate Year-to-Date Totals
One of the most common use cases of the STARTOFYEAR function is to calculate year-to-date totals. To do this, you can use the following formula:
YTD Sales = TOTALYTD([Sales], ‘Date'[Date], ALL(‘Date’), “1/1”)
In this formula, "Sales" is the name of the column containing your sales data, and "Date" is the name of the column containing your date values. The STARTOFYEAR function is used to specify the start of the year as January 1st. This formula will calculate the total sales from January 1st to the current date.
Example 2: Compare Sales Across Years
Another way to use the STARTOFYEAR function is to compare sales across different years. To do this, you can use the following formula:
Sales LY = CALCULATE([Sales], SAMEPERIODLASTYEAR(‘Date'[Date]))
In this formula, "Sales" is the name of your sales column, and "Date" is the name of your date column. The STARTOFYEAR function is not explicitly used in this formula, but it is used implicitly by the SAMEPERIODLASTYEAR function, which returns the same period of the previous year as the current period. This formula will calculate the sales for the same period of the previous year.
Example 3: Highlight Data for the Current Year
You can also use the STARTOFYEAR function to highlight data for the current year in your visualizations. To do this, you can use the following formula:
Highlight Current Year = IF(YEAR([Date]) = YEAR(STARTOFYEAR(TODAY())), “Current Year”, BLANK())
In this formula, "Date" is the name of your date column. The TODAY() function is used to get the current date, and the STARTOFYEAR function is used to get the first day of the current year. This formula will return the string "Current Year" for dates in the current year, and a blank value for all other dates.
The Power BI DAX function STARTOFYEAR is a versatile tool that can be used to analyze data in a variety of ways. Whether you are calculating year-to-date totals, comparing sales across years, or highlighting data for the current year, this function can help you make sense of your data and make informed business decisions. With the examples provided in this article, you should have a good understanding of how to use the STARTOFYEAR function in your Power BI reports.