Abstract
On the basis of measurements on the road of cars, with drivers instructed to car-follow in different ways, three types of car-following have been discriminated: short-following, normal-following and long-following. With an estimation of the distribution of the three car-following types per roadlane type and volume we try to explain phenomena as capacity-funneling and the "two-regimes-theory", and the probability of hourly volumes greater than saturation flow.