Obsolete Memory Storage

  If I could only delete unneeded stuff that's stored in my memory, that should open up a space to store current information, shouldn't it? For instance, I have absolutely no reason to know  that my college Student Number was 21293.  That  was once a vital identification number, used on every reference to academic performance, but that was a very long time ago. I have no reason to be able to recall that the first license plate on my father's car that I was able to read was 7A-3535. I'm not even sure of the license plate number on the car I drive now. If I could just substitute one for the other.  And  I know that my sister's first telephone number when she married and left home was 235-3299.  That was the first number listed in the Telephone Directory after she moved and had a new number.  It belonged to AAA Ace Services or something like that.