Year over Year Variance Calculation Error "EARLIER/EARLIEST" refers to an earlier row context which doesn't exist - powerbi

Question

While trying to calculate Year over Year variance (unsuccessfully for 2 days now), I get the following error message.
EARLIER/EARLIEST refers to an earlier row context which doesn't exist.
YOY Variance = var PreviousYearPrinBal = CALCULATE(SUM(Deals[Principal Balance]),FILTER(ALL(Deals[Close Date].[Year]),Deals[Close Date].[Year] = EARLIER(Deals[Close Date].[Year])))
return
if(PreviousYearPrinBal = BLANK(), BLANK(), Deals[PrincipalBalance] - PreviousYearPrinBal)
In a different SO question, there is a different approach which gives me the following error:
A column specified in the call to function 'SAMEPERIODLASTYEAR' is not of type DATE. This is not supported.
yoy = CALCULATE([PrincipalBalance], SAMEPERIODLASTYEAR(Deals[Close Date].[Year]))
While I have some idea of what these mean, I do not have an idea of how to fix them. Here is my table.
And Here is what I expect as the result.
I've tried posting this question in Power BI community but haven't received an answer yet. Calculate Year over Year Variance.
ACTUAL DATA SAMPLE:

Answer 1

1) Created Year and Year Difference Column (Calculated Column)
Year = YEAR(Table1[Date])
Year Difference = Table1[Year] - Min(Table1[Year])
2) Created the Variance (Measure)
Variance =
Var current_YearDifference = SELECTEDVALUE(Table1[Year Difference])
Var Current_PrincipalBalance = CALCULATE(SUM(Table1[Principal Balance]),FILTER(ALL(Table1), Table1[Year Difference] = (current_YearDifference)))
Var Previous_PrincipalBalance = CALCULATE(SUM(Table1[Principal Balance]),FILTER(ALL(Table1), Table1[Year Difference] = (current_YearDifference - 1)))
Return if(current_YearDifference <> 0, (Current_PrincipalBalance - Previous_PrincipalBalance), 0)
3) Finally Created the Variance in terms of Percentage (Measure),
Variance in terms of Percentage =
Var current_YearDifference = SELECTEDVALUE(Table1[Year Difference])
Var Current_PrincipalBalance = CALCULATE(SUM(Table1[Principal Balance]),FILTER(ALL(Table1), Table1[Year Difference] = (current_YearDifference)))
Var Previous_PrincipalBalance = CALCULATE(SUM(Table1[Principal Balance]),FILTER(ALL(Table1), Table1[Year Difference] = (current_YearDifference - 1)))
Return if(current_YearDifference <> 0, ((Current_PrincipalBalance - Previous_PrincipalBalance) / Previous_PrincipalBalance), 0)
My Final Output
The Principal Balance has the function SUM selected on the Values Pane of the Output Table, where as the Year is Don't Summarize.
My Best Practice
Always Use Vars when creating Complex Measures to simplify the
formula.
Then return only a part of the Measure to check if the output is as expected.
Kindly let me know, if it helps or not.