What Times of Day are the Most Dangerous to be Driving?

With the frequency that they occur, I thought it would be interesting to graph how many crashes occur at each time of day. From the graph, it's clear that most crashes occur in the afternoon. That makes sense given that it's around rush hour. A significant amount of crashes also occur between 8 and 11:59 pm, when you wouldn't expect many people to be driving, which may suggest that because visibility is lower or their may be a higher proportion of intoxicated drivers on the road during this time, that more crashes could occur despite there being fewer drivers on the road relative to the afternoon.