Depending on what the data type of the column is you could do it using dateadd or replace as shown below. If your column is datetime type (and assuming you want to replace all rows etc.)UPDATE YourTable SET YourDateCol = DATEADD(YEAR,36,YourDateCol); -- add 36 years
If it is character type:UPDATE YourTable SET YourDateCol = REPLACE(YourDateCol,'1975','2011');; -- replace 1975 with 2011