Urban Migration and Demographic Trends in Thailand
Thailand's urban population as a percentage of the total population remains lower than the world average. Urban population in the world surpasses the 50 % mark a few years ago. In Thailand in 2017 we are about to reach that threshold. [Data provided by World Bank website, reportedly based on Thai data]
Urban population in Thailand was only around 20 % in 1960. Since then there has been a steady increase which accelerated a lot from the year 2000. From then on the percentage of city dwellers increased from 31.4 % to 49.2 %. This is around 1 % of the population moving every year (or around 600,000 people!).
If the numbers are correct, it means that lots of people are moving from the countryside. It must mean that fewer and fewer people will be working in the agricultural sector.
When looking at the different regions of Thailand, we can see striking differences. Most prominent and well known locally, is the profound increase in the population of Bangkok and its surrounding provinces (treated as one huge 'metropolis' here). The population there increased from 9,809 million to 15,759 million, an increase of 60.7 %. Lets also state that the overall population of Thailand increased from 59,595 million to 67,455 million or 13.2 %, (fertility rate in Thailand is around 1.5 % since many years, meaning that the population will start to decrease not that long from now).
In absolute numbers the same 20 years saw a prominent decrease in population of the Northeastern Region of Thailand. Isaan saw its population decrease from 20,439 million in 1996 to 18,674 million in 2016, a decrease of 8.6 %. Please take into account that Thailand's population overall increased by 13.2 % during that period. The population of the Northeast actually increased till the year 2000, so the decrease in population since than is even larger percentage-wise. Looking at the first image on this page, it likely explains a lot about the increase in urban populatoin from the year 2000 onwards.
It is not likely that fertility in the Northeast is much lower than elsewhere in the country. What is more likely is that most of the migrating people ended up in Bangkok and surrounding areas. From the absolute figures it is not quite possible to tell how much of the increase in population of the Eastern Provinces comes from the Northeast, or maybe from Bangkok or other provinces.
When looking at the percentual increase of the population in the different regions of Thailand, it also becomes clear that there has been a large relative increase in the population of the Eastern provinces. The population in the East increased from 3.866 million to 5,633 million from 1996 to 2016, an increase of 45.7 percent.
These migration patterns are most easily explained by the 'follow the money' principle. The Eastern Region is an area of heave (petrochemical and other) industry, and Bangkok is kind of a center of all things going on in Thailand, except perhaps for the agricultural industry.
Map delineating the above described regions. You can also find the location of the provinces at our page regarding provincial GDP (GRP) :