Strength of schedule is calculated from the opponents projected fantasy points allowed for the RB position. The best rating is +16 which gives the player the advantage against the defense and indicates an easy opponent, the worst rating is -16 which gives the defense the advantage and indicates a tough opponent.
Bush is now 30 and his 3.9 yards per carry last year was the lowest average he's put up since 2008. The days of Bush trying to be a feature back are over. That doesn't mean his fantasy value is dead though. The 49ers brought Bush in to be the lightning to Carlos Hyde's thunder. Hyde will get most of the early down work, while Bush will handle the passing down duties. Bush has caught at least 40 passes in seven of his nine seasons. He'll have a big impact in PPR formats.