30 day Readmission: Date difference between first discharge and readmission

Marit585  So i formatted the data as a table and used 'Text to Columns' to force the dates in the date columns to format as dates and not text (maybe your version recognizes them as dates already).  Then I created a column that calculates the Time since last Dischaarge using a formula that will filter all the discharge dates based on uniqueID, sort them and find the closest that is less than the receive date and take the difference.  Then I created a column that gives a T/F based on it being <=30.  It could be done in 1 column but I think that Time since last Discharge could be valuable.