OK, plan B.
Make a table of dates imported from excel for all the dates in 2018, so 365 records. We can worry about the other years later.
Set the key field to be the date.
Make a relationship back to your sales detail data based on the date field and then summarize up to the Dates table the sales for each day. Call that field [Today's Sales]
Now comes the funky part.
Make a new relationship of the dates table to itself based on a formula date field called [Yesterday] with the formula of [date]-days(1)
Make a new formula field called field called [YTD Sales] (blank formula for now).
Look up that field from that self referential relationship and call the lookup field [Sales YTD to Yesterday]
Set the formula for the field [YTD sales] to be [Sales YTD to Yesterday] + [Today's sales]
Now when you list any of the date records, (say for a month or a quarter) they can show the sales for that date as well as the YTD sales.
It's a daisy chain where each date looks up data from the previous date.
