Here's an example syntax that you can adapt to your specific data:

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* Compute earliest date variable.

COMPUTE earliest_date = MIN(date1 TO date100).

EXECUTE.

* Compute latest date variable.

COMPUTE latest_date = MAX(date1 TO date100).

EXECUTE.

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In this syntax, the MIN() function is used to compute the earliest date across the date1 through date100 variables for each case, and the MAX() function is used to compute the latest date across those variables. The results are saved in new variables called earliest_date and latest_date, respectively.

Note that you should replace date1 and date100 with the actual variable names that correspond to the dates in your data.

Also, make sure that the variables are in the correct format (e.g., date format) before computing the earliest and latest dates.

Hope this helps.

Thanks a lot! Very helpfull.

When I used this syntax, my new date variable is not recognisable as a date. My orginal date variables are all in dd-mm-yy format (09-aug-22).

For example the syntax for the latest date gave in the first row: 13867414916.00

I Used: ALTER TYPE latest_date (date10).

Then it turned into 23-Mar-22.

Any idea what caused this? Thanks again!

Miriam van der Velde Glad it was helpful.

The issue you're encountering is likely due to the fact that the MIN() and MAX() functions are returning the minimum and maximum values across the range of dates, rather than the actual earliest and latest dates. To convert these values to dates, you can use the DATE() function in SPSS. Here's an example syntax that you can use to compute the earliest and latest dates for each case:

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* Compute earliest date variable.

COMPUTE earliest_date = DATE.MIN(date1 TO date100,"DMY").

EXECUTE.

* Compute latest date variable.

COMPUTE latest_date = DATE.MAX(date1 TO date100,"DMY").

EXECUTE.

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In this syntax, the DATE.MIN() and DATE.MAX() functions are used to compute the earliest and latest dates across the date1 through date100 variables for each case. The second argument of these functions specifies the format of the dates in your data (in this case, "DMY" for day-month-year format).

Note that the DATE() function automatically converts the numerical value returned by DATE.MIN() and DATE.MAX() into a date value in the format specified by the second argument. Also, be sure to double-check that the format of the new earliest_date and latest_date variables is correct. You can use the FORMATS command to set the format for these variables if necessary. For example:

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* Set format for earliest_date and latest_date variables.

FORMATS earliest_date latest_date (DATE10).

EXECUTE.

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Let me know how that works.