What is the proper way to connect a periodic snapshot table to a date dimension?

I have a fact table with monthly budget forecast. The "book" says I should connect to the date dimension using the last day of the month. I was thinking that since these are forecast figures I should use the beginning of the period. Or should I take the third option and crate a month dimension and populate it with month and year instead of the standard date dimension?

Hi,

you can use the begining of the month, if that works as the budget forecast is monthly. You dont need to create a sepearte dimension as you can pick up the starting month date from the current dimension.

thanks