A simple but structured approach would be:
- Start from the population of Dubai (let’s assume 3 Mln)
- Assuming on average 2.5 people in each household
- Therefore, we have 1.2 Mln of households (i.e. apartments)
- Assuming that on average in Dubai there are 40 apartments for each building
- Therefore, we have 30k residential buildings
- Assuming that on average every 16 buildings there is 1 street intersection
- Therefore, we have a total of 1,900 intersections in Dubai
- Assuming 4 traffic lights for each intersection
- Finally, we can estimate roughly 7,600 traffic lights in Dubai
Naturally, this is just one of several possible approaches.
It is always good to ask preliminary questions to the interviewer and understand if he/she is comfortable with the type of approach we are undertaking; likewise, is always a good practice to share with the interviewer all the assumptions we need to consider along the whole process of market size.
Hope this helps,