In North America, the term light rail generally refers to urban rail systems that do not require full grade separation and can range from street-running to heavily grade separated networks. There is no universal definition of "light rail transit systems", so some systems (such as Toronto's) are technically streetcars rather than "true" light rail.
Daily ridership figures for American and Canadian light rail systems are defined as "average weekday unlinked passenger trips" (where transfers between lines are counted as two separate passenger "boardings" or "trips"), unless otherwise indicated. For light rail systems in the United States and Canada, these figures come from the American Public Transit Association (APTA)'s quarterly statistics. For Mexico, the figures are obtained from Banco de Información Económica's Instituto Nacional de EstadÃÂsitica y GeografÃÂa (INEGI), and the daily figures represent daily passenger trips averaged from the monthly and quarterly ridership figures. "Daily boardings per mile" figures have been rounded to the nearest 5 or 10.
The following systems have been excluded from the ridership table above (generally because the system's ridership statistics are not tracked by APTA):