Population in the city has come a long way from just a few thousands in 1903 to almost three million in 2000 (Table 2.06). Although population is continuously increasing, the growth rate has been seesawing at various degrees as can be seen in Fig. 2.02. Tremendous increase in growth rates can be noted in census years 1948-1960 and 1960-1970, the former a period of postwar reconstruction and the latter witnessing a historical event as Mandaluyong became part of the Greater Manila Area. It was during both these periods when population count more than doubled in Mandaluyong.

The next time population will double is in about 60 years, given a growth rate of 1.15% for the 10-year period between 1990 and 2000.

It could be noted however, that population growth rate between 1995 and 2000 is valued as (-) 0.64. This decrease can be attributed to population movements within and outside the city as can be observed in succeeding topics.

During the last two decades, barangay populations in the city were never stationary. While rapid population growth is often associated with the decline in mortality due to milestone achievements in science and technology without the corresponding decline in fertility, migration has always played an important role in shaping up the trends in population.

A review of population and housing programs for the last five years shows that a number of families were relocated from one barangay to another. Consequently, there was a decrease in population of the barangays of original residence and an increase in population of the receiving barangays. Other relocatees were sent elsewhere outside Metro Manila. However, the possibility of migrating in one’s own accord should also be considered.

Comparing results of four censuses, it can be noted that population of Addition Hills over the 20-year period has increased by about 450 percent. The 1980 figure has actually doubled after ten years, and again doubled by the year 2000. This is attributed to the fact that Addition Hills is the second largest barangay in the city in terms of land area, and is host to the Welfareville Property which at the moment is home to tens of thousands of informal settlers. Welfareville is actually the largest informal settlement of the country and is classified as a Planned Unit Development area.

Another barangay which registered a significant population increase is Hulo, which, over the 20-year period has increased from 13,996 (1980) to 20,585 (2000). This record a 68 percent (67.99%) increase (Table 2.07).