If you are implying that despite their superior driving skills and care for safety the bus drivers suffer from crazy drivers just ramming them due to being a bi

If you are implying that despite their superior driving skills and care for safety the bus drivers suffer from crazy drivers just ramming them due to being a big target then I'd advise you to compare accident rate on delivery trucks - they are roughly the same size as busses and drive the same streets in the same manner (with a lot of stops). I don't see any published study but it's easy to pull crash reports from the carriers, they are surprisingly similar at ~0.4 per 1M miles, much lower than cars.