"But, every year after 1956, every criterion of subway performance - on-time runs, individual car breakdowns - disclosed that the toll was steadily mounting. By the late 1960s, the day of full reckoning had arrived. 17,070 runs had to be halted during a single 8mo period. 45 cars were breaking down on an average day. 40 trains were derailed in a single year."

Don't even have space to describe the deaths and horrors that happened, described in the book..