Custom conditional formatting

Hi Justas4478 

What exactly do you mean by the latest value for each month? So, if the most recent date with a value in December is the 31st and that value is 1, would you use that value? Then, would you compare it with the corresponding value from the previous month?

If you simply want the compare the value of this vs previous months value, try:

Conditional formatting color =
VAR _PrevMonth =
    CALCULATE ( [my measure], PREVIOUSMONTH ( datestable[date] ) )
VAR _Difference = [my measure] - _PrevMonth
VAR _Color =
    IF (
        NOT ( ISBLANK ( _PrevMonth ) ) && NOT ( ISBLANK ( [my measure] ) ),
        IF ( _difference > 0, "green", IF ( difference < 0, "red" ) )
    )
RETURN
    _Color

Select field value from conditional formatting option and use the measure above. You may replace red or green with RGB, RGBA or hexadecimal values.