Preflop Raise % — how often you enter the pot with a raise. Close to your VPIP = an aggressive, raise-first style; a big gap means you flat-call too much.
A healthy player raises most hands they play rather than limping in. If VPIP is 24 and PFR is only 10, you are open-limping or cold-calling a lot — passive, and it forfeits the initiative that wins pots. Aim to keep the VPIP–PFR gap small.