Do this:

define cprtxt __________ // string of length 10 define yrtxt __ // string of length 2 cprtxt = cpr yrtxt = copy(cprtxt,5,2) // digits 5 & 6 select yrtxt = "40"

This can also be done in a single line, if you have no other use for the year of birth:

select copy(cpr,5,6)="40"

Jamie Hockin

2009/10/27 Jes Lindholt wrote:

In Denmark, we have the unique CPR number consisting of birthdate (ddmmyy) followed by 4 numbers. If I have to select a population born in fx 1940 from a larger epidata-fil, I consider to use the export facility, but then need an observation filter only selecting those born in 1940, which means those numbered 40, in position 5 and 6 in the 10 digit CPR variable. Do anybody have knowledge of a relevant syntax for that?