about past perfect tense

Welcome anybody to tell me is the sentence below correct or not using past perfect tense.

I went to college in the year 2000
        after I had worked as a temporary worker in
        the year 1999.

I am puzzled about the sentence because there are two specific dates--the year 2000 and the year 1999-- in it.

I am not sure that:

do we need past perfect tense here to show the timing sequence of the two actions,

or can the two specific dates themselves clearly tell the timing sequence, so we don't need to use past perfect tense? 

Hope for your comments and thank you in advance.