They don't describe the graphic very well in the article, but they do link to the source data [1]. The "Expected" line seems to refer to a historical average. S

They don't describe the graphic very well in the article, but they do link to the source data [1]. The "Expected" line seems to refer to a historical average. Since the starting point of the graph coincides with the beginning of congestion pricing, we would expect a difference between the two values at that point. [1] https://metrics.mta.info/?cbdtp/vehiclereductions https://metrics.mta.info/?cbdtp/vehiclereductions