Vehicle statistics: time spent on task per resource

Currently, vehicle statistics feel very much useless to me, because there is no way to find out how much time is spent on which resource. For example, I had one of my dumps lacking more designations, which resulted in trucks driving around an around 10 times longer distance to dump.
If truck logistics is severely overloaded, I can't use statistics to figure out which resource is the cause - a resource with very long distance may have low throughput, but bind trucks for a long time, even up to months for a single shipment.
I would really like a statistic that shows how many days trucks spend on which resource.
It should even be fairly performance friendly, just make an array of how many trucks are currently on the way to fetch each resource, another for how many are currently delivering (I think that split would have been important information for me fairly often), then periodically add those numbers to a "truck days spent per resource" list. That would have been so useful so often...

Same thing for me. The number of trips doesn't give relevant information for solving the overload issue.

"Days trucks spend on which resource" or distance. But the distance of the full path.