My 20-year-old daughter's scores took 15-20 point jumps when her student loans appeared. All that she had before that were credit cards.
In some scoring buckets, the scoring formula actually wants you to add credit. One good way of seeing what's what is to play with the simulators on EQ and TU --slide down to the options involving applying for and getting new credit.
The sims predicted her score increases.
It's very important to realize that each person's scores react in individual ways, depending on their particular credit profile.
* Credit is a wonderful servant, but a terrible master. * Who's the boss --you or your credit?
FICO's: EQ 781 - TU 793 - EX 779 (from PSECU) - Done credit hunting; having fun with credit gardening. - EQ 590 on 5/14/2007