Hi I have many excel files were the Date field was not declared as date, so the dates look like this: 1/2/1978 I know that the format is day/month/year How can I make R change this to Date format? If I use strftime, I get wrong dates: dataset=c("1/2/1978") strftime(dataset,"%d/%m/%Y") "19/02/0001" Thanks in advance.