Finding cummulative sum of MAX values - max

Question

I need to calculate the cumulative sum of Max value per period (or per category). See the embedded image.
So, first, I need to find max value for each category/month per year. Then I want to calculate the cumulative SUM of these max values. I tried it by setting up max measure (which works fine for the first step - finding max per category/month for a given year) but then I fail at finding a solution to finding cumulative SUM (finding the cumulative Max is easy, but it is not what I'm looking for).
Table1
Year Month MonthlyValue MaxPerYear
2016 Jan 10 15
2016 Feb 15 15
2016 Mar 12 15
2017 Jan 22 22
2017 Feb 19 22
2017 Mar 12 22
2018 Jan 5 17
2018 Feb 16 17
2018 Mar 17 17
Desired Output
Year CumSum
2016 15
2017 37
2018 54

Answer 1

This is a bit similar to this question and this question and this question as far as subtotaling, but also includes a cumulative component as well.
You can do this in two steps. First, calculate a table that gives the max for each year and then use a cumulative total pattern.
CumSum =
VAR Summary =
SUMMARIZE(
ALLSELECTED(Table1),
Table1[Year],
"Max",
MAX(Table1[MonthlyValue])
)
RETURN
SUMX(
FILTER(
Summary,
Table1[Year] <= MAX(Table1[Year])
),
[Max]
)
Here's the output:
If you expand to the month level, then it looks like this:
Note that if you only need the subtotal to work leaving each row as a max (15, 22, 17, 54) rather than as a cumulative sum of maxes (15, 37, 54, 54), then you can use a simpler approach:
MaxSum =
SUMX(
VALUES( Table1[Year] ),
CALCULATE( MAX( Table1[MonthlyValue] ) )
)
This calculates the max for each year separately and then adds them together.
External References:
Subtotals and Grand Totals That Add Up “Correctly”
Cumulative Total - DAX Patterns