Fill empty column rows with max of other rows

[Brotedo]

I have a dataset with monthly sales numbers that correspond to a month index 1-12. I want the sales number for the current and future month to always display as the max of the previous months.

For example, if the current month was 4, what I have now is this:

1	40
2	55
3	83
4	0
5	0
6	0
7	0
8	0
9	0
10	0
11	0
12	0

but I want this

1	40
2	55
3	83
4	83
5	83
6	83
7	83
8	83
9	83
10	83
11	83
12	83

For what it's worth, the sales are cumulative, so the max number will always be the month right before the current month.

[amitchandak · Accepted solution]

@Brotedo , With help from separate date/month table joined to your table used in visual and formula

a measure like

Cumm Sales = CALCULATE(SUM(Sales[Sales Amount]),filter(all('Date'),'Date'[date] <=max('Date'[date])))

or

Cumm Sales = CALCULATE(SUM(Sales[Sales Amount]),filter(allselected('Date'),'Date'[date] <=max('Date'[date])))

or

Cumm Sales = CALCULATE(SUM(Sales[Sales Amount]),filter(all('month'),'month'[month] <=max('month'[month])))