10-24-2013 09:24 PM
2000 2010 2013
format b_date m_date e_date mmddyy10.;
10-25-2013 02:10 AM
A date variable in SAS is just another numeric variable. To be meaningful as a date the value is defined as the number of days between January 1st 1960 and the date the value is representing. Therefore is you take your existing numeric value of the year 2000 and try to use it as a date (e.g. in a date function or formatted for display) this will represent 2000 days from January 1st 1960, which is somewhere in 1965 :-)
To 'convert' it to a date you need to convert it to an appropriate number of days. This is what the function mdy is doing in Linlin's response. This function takes 3 arguments: months, days, years. As you only have the year, you need to decide at what point during that year you want to represent the date, e.g. beginning, middle, end, or any other point you choose.
You can then use your modified value with date formats or functions as you like.
Hope that helps