days between previous date in a column based on condition of another column

[wes-shen-poal]

Hi there,

I would like to create a new column, called Days_between_visits which calculates the number of days between a date in the ATA (Actual Time of Arrival) column and a previous date also in the ATA column, for each vessel in the VesselName column

For the first date of each vessel, Days_between_visits would be null as there is not previous date to calculate the difference with.

Is this possible? If so, please kindly assist with the DAX formula required the calculated column

Thanks,
Wes

[Phil_Seamark · Accepted solution]

HI @wes-shen-poal

I think this calculated column might be close

New Column = 
VAR LastVisit = MAXX(
            FILTER(
                'Table',
                'Table'[VesselName] = EARLIER('Table'[VesselName]) && 
                'Table'[ATA] < EARLIER('Table'[ATA])),'Table'[ATA])
RETURN IF(LastVisit <> BLANK(),INT('Table'[ATA] - LastVisit))

[Anonymous]

@Phil_Seamark I found this solution very helpful, but I had 2 rows that did not return a value that should have. Do you know why this might of happened?

[wes-shen-poal]

Hi @Phil_Seamark

This is perfect. Thank you so much for your help.

Wes