How many cars are on Kenyan roads?

By MUNGAI KIHANYA

The Sunday Nation

Nairobi,

20 April 2008

Geoffrey has a seemingly straightforward question: “How many cars are on Kenyan roads? I’ve been feeling a bit crowded on the road on my way to work” However, since the abolition of motor vehicle road licenses, it is difficult even for the Registrar of Motor Vehicles to get an accurate figure. The reason being that people will buy cars and throw them away without informing the authorities!

But still, we can get a fairly accurate answer by making assumptions on the lifetime of cars on Kenyan roads and estimating the number of new registration per year. The product of these two quantities gives the vehicle population.

Industry experts maintain that a brand new car “lives” for about 20 years. (Some will live to 25 and others will die at age 15.) From that estimate, we can work out the life of a second hand imports to be about 15 years – since they are and five years old at the time of importation.

With these two values, one might be tempted to say that the average life of a car in Kenya is 17.5 years – the mid-point of 15 and 20; but that would be wrong. The reason is that the numbers of the two categories of vehicles are not equal. There are more second-hand imports (about 75 percent of the total) than brand new models (25 percent).

Thus, the correct way is to calculate the “weighted average” lifetime. The assumed ratio of 75 percent to 25 percent means that there is one new vehicle for every three second hand ones. Therefore, we should multiply the lifetime of used imports by three, add that of new cars and divide the result by four. That is, 15 x 3 = 45; 45 + 20 = 65; 65 / 4 = 16.25 years.

Having estimated the average lifetime of cars, the next step is to find the approximate number of registrations per year. Clearly, the estimation should only be done over a duration equal to the mean life span. That is, the 16 years from 1992 to 2007 (if you doubt it, count them starting with 1992).

The exact registration data is in the records of the Registrar but getting it out may not be easy. So again we estimate it as follows: last year there were approximately 80,000 new registrations; in 1992, the figure was about 24,000. Thus, assuming a smooth and gradual increment, the annual average is 52,000.

The final step is to simply multiply 52,000 and 16 years. The result is 832,000 cars. However, this is a figure obtained from many estimations and assumptions. Thus is might be significantly higher or lower than the actual value. All the same, it makes one understand why there are so many cars all over – especially when we remember that most of our roads were built in the 1970s and 80s.