Complex sentence: Ridership was very low in the early years, averaging less than 10,000 riders per day as it was not finished, even after nearly one billion dollars in federal subsidies, meaning that US $100,000 was spent for each passenger.
Split into simpler sentences: Ridership was very low in the early years, averaging less than 10,000 riders per day. The system was not finished, even after nearly US $1 billion in federal subsidies, meaning that approximately US $100,000 was spent for each passenger.