Some may choose to take the slightly slower to the city with a city, rather than being dumped at Marylebone station (not passing go), which has pretty poor tube

Some may choose to take the slightly slower to the city with a city, rather than being dumped at Marylebone station (not passing go), which has pretty poor tube connections (or is a walk outside to Baker Street to catch a standing only tube) Only way to work it out would be specific data (like axel weights), which may be whats generating the data sets.