Microsoft Power BI - DAX Time Intelligence measure - change context to reflect proper % change; non-YTD measures - time

Question

I have a Power BI visual as below. There are 3 matrices. I have a DateDimension (or) Calendar table called Dates2.
I use two measures, one a regular measure (called 'Count'), the other a parallel period comparison of the measure (called 'Count_PreviousYear'). I use SAMEPERIODLASTYEAR DAX function for the latter.
1)
Count = COUNTA(TableX[ColumnY])
--Measure with name 'Count'--
2)
Count_PreviousYear = CALCULATE
(
[Count],
SAMEPERIODLASTYEAR(Dates2[Date])
)
--Measure with name 'Count_PreviousYear'
--this measure uses Time Intelligence function - SAMEPERIODLASTYEAR--
Both 'Count' and 'Count_PreviousYear' (obviously) are not YTD (YearToDate) values.
A third measure for the percentage change across periods is computed as below:
3)
PercentageChange = IF(
ISBLANK([Count]) || ISBLANK([Count_PreviousYear]),
BLANK(),
(([Count] - [Count_PreviousYear])/[Count])
)
Kindly ignore the fact that a keyword used as a measure name;
I have used the name 'Count' only for clarity; in my actual report,
I have proper names
The % change measure works fine, but one issue:
For the period change from 2020 to 2021, i.e. in the third row of the last matrix (for the row value 2021), the total (i.e. the % change value) is not appropriate.
I need to replace -737.21% with - 23.98 %.
This is because , I need to compute the Total for 2020, only by adding the values for the months of January and February, i.e. 428 + 430 = 858. (not 5794, which is for all the 12 months).
Since 2021 has only two months - January and February, I don't want to compare two months of 2021, with all the 12 months of 2020. Rather, I want two months of 2021 to be compared with the corresponding 2 months of 2020.
Essentially I need {(692-858)/692} * 100 = -23.98%
Currently, I see {(692-5794)/692} * 100 = -737.21%
Can someone help me achieve this?

Answer 1

Count Previous Year =
IF (
HASONEVALUE ( Dates2[Month] ),
IF (
[Count] <> BLANK (),
CALCULATE ( [Count], SAMEPERIODLASTYEAR ( Dates2[Date] ) )
),
IF (
HASONEVALUE ( Dates2[Year] ),
CALCULATE (
[Count],
DATESBETWEEN (
Dates2[Date],
EDATE ( MIN ( Dates2[Date] ), -12 ),
EOMONTH ( MAX ( [FactTable[Date] ), -12 )
)
)
)
)

Answer 2

Count_PreviousYear = IF (
(HASONEVALUE(Dates2[Year]) = TRUE && HASONEVALUE(Dates2[MonthName]) = TRUE),
CALCULATE
(
[Count],
SAMEPERIODLASTYEAR(Dates2[Date])
),
IF (
(HASONEVALUE(Dates2[Year]) = TRUE && HASONEVALUE(Dates2[MonthName]) = FALSE),
CALCULATE (
[Count],
DATESBETWEEN (
Dates2[Date],
EDATE (MIN(Dates2[Date]), -12),
EOMONTH (MAX(SourceData[Date]), -12)
)
),
BLANK()
)
)
!Output obtained as desired]1