Where does the problem comes from?? Maybe from my sytem date ??
Simply from not reading the options carefully enough, from ?strptime, ‘%y’ Year without century (00-99). If you use this on input, which century you get is system-specific. So don't! Most often values 00 to 68 are prefixed by 20 and 69 to 99 by 19 - that is the behaviour specified by the 2001 POSIX standard, but it does also say ‘it is expected that in a future version of IEEE Std 1003.1-2001 the default century inferred from a 2-digit year will change’. ‘%Y’ Year with century. You want %Y, not %y. ______________________________________________ R-help@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.