There's an element of control when you're in a personal vehicle that's lacking when you're on transit with the general public, and fatalities aren't necessarily the only risk factor to be considered.
e.g. I'm less likely to be mugged or assaulted in a personal vehicle compared to public transit but I'm also more likely to have my vehicle broken into or stolen. Public transit is also _very_ different during typical commute times, compared to off hours.
e.g. I'm less likely to be mugged or assaulted in a personal vehicle compared to public transit but I'm also more likely to have my vehicle broken into or stolen. Public transit is also _very_ different during typical commute times, compared to off hours.