INTNX is the correct function, however argument #1 needs to be "DTHOUR" for a SAS DATETIME variable. If your input data-string is a SAS CHARACTER variable, then you need to convert it to a SAS numeric type DATETIME variable, likely in a DATA step. One way is to split up the string into the DATE and TIME portions, then use the SAS INPUT function in assignment statements to convert each component, and then use a DHMS function to create your SAS DATETIME numeric variable.
Scott Barry
SBBWorks, Inc.
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