I would like to build a data.frame with a column of POSIXct dates orderly differing one day per row exactly, that is: Data dato1 01/06/2005 ....... 02/06/2005 ....... .............. 29/06/2005 ........ 30/06/2005 etc giving the extreme dates 01/06/2005 & 30/06/2005. How can i obtain this result? Vittorio