Complex sentence: They claimed that they were losing $80,000 a year from continuing the train to Ishpeming--even peak service times, e.g. when the service required an additional five passenger cars during the holiday season eight years later, were not enough to sustain a yearly profit.
Split into simpler sentences: They claimed that they were losing $80,000 a year from continuing the train to Ishpeming--even peak service times. The service required an additional five passenger cars during the holiday season eight years later, were not enough to sustain a yearly profit.