And if you want to get a feel for what PC was up against operationally day to day in it's short eight years, read Taylor's superb " A Sampling Of Penn Central." While not comprehensive regarding the whole road (only covers three divisions on the west end) it has a most unusual horizontal format discussing route rationaliztion, traffic patterns, customers etc. in plain language coupled with matching horizontal page size B&W photo. At some two hundred plus subject pages there are very few books on any road that equal it in detail. In short amazing and yes , one finishes it realizing the passenger issue was one of the least of the road's problems, in part due to the subject division locations (CHi-Cinn, St.L-Cleve etc) as opposed to the commuter and intercity heavy NorthEast. On the other hand , the PC had to retain a lot of otherwise superflous trackage merely to support the PRR/NYC remnant passenger and later Amtrak services. But again, not even close to the real issues financially killing it then daily.
Perhaps, most sadly, reading it makes one realize how many factories really have gone "adios" in Ohio, Indiana and West Virginia.