Forecasting with Parameters from Historical Data

Step 1) Change the relationship so Calendar table will filter the fact_table.

Step 2) Create DateType column in Calendar table that holds an information if it's a forecast or actual value.

Growth Rate - Dynamic = 
VAR __lastDateWithActual = CALCULATE(MAX('Calendar'[Year]),'Calendar'[DataType]="Actual")
VAR __thisyear = MAX('Calendar'[Year])
VAR __GrowthRatePerDepartment = 
    CALCULATE(
        AVERAGEX(
            VALUES(fact_table[Department]),
            SWITCH(fact_table[Department],
            "Business",Business[Business Value],
            "Science",Science[Science Value],
            "Technology",Technology[Technology Value],
            "Math",Math[Math Value],
            "History",History[History Value],
            1)
        ),
        ALL('Calendar')
    )
VAR __compundGrowRate = 
    CALCULATE(
        PRODUCTX(VALUES('Calendar'[Year]), 1 + __GrowthRatePerDepartment),
        'Calendar'[Year] <= __thisyear,
        'Calendar'[Year] > __lastDateWithActual
    )
RETURN __compundGrowRate