The Census of Population and Housing takes an inventory of the total population and housing units in the Philippines and gathers information about their characteristics.

1570-1800s During these periods, population count was determined largely by estimates rather than actual counts. The earliest estimate which placed the population at half a million was made by Dr. D. P. Barrows, Chief of the Bureau of Non-Christian Tribes. This was for the year 1570, at about the time of the conquest of the islands by Legaspi.

In 1591, the population was estimated at 667,612 based on the number of tributes comprising an encomienda. About 166,903 tributes were counted, each representing four persons on the average. This was the only estimate based upon encomiendas as the system ceased in 1600.

Later, population estimates depended on church records since people were distributed by parish among religious orders. With records of baptisms, marriages and burials as the source, only the Christian population was counted. In 1799, Father Manuel Buzeta estimated the Christian population at 1,502,574.

1878 The first official census in the Philippines was carried out by the Spanish government pursuant to a royal decree calling for the counting of persons living as of the midnight of December 31, 1877. The census yielded a population count of 5,567,685.

1888 and 1898 Two more censuses, similar to that undertaken in 1878, followed by orders of separate royal decrees. The population for 1887 was counted at 5,984,727.In 1898, the population, as published in the Guia Official, was placed at 5,279,955. The census operation during that year was abandoned when war erupted between the Spaniards and the Americans.

1903 The census was conducted on March 2, exactly a year after the establishment of the civil government. This was conducted to fulfill Act 467 which was approved by the U.S. Congress in July 1902. The census covered the whole Philippine Islands and the actual gathering of data took about two months. The population was counted at 7,635,426.

1918 This was the first census in the Philippines undertaken by an all-Filipino crew from the directorship down to the lowest level. By proclamation of the Governor-General, Census Day was scheduled on December 31, 1918. The population was counted at 10,314,310.

1939 This census was undertaken in conformity with Section 1 of C. A. 170. It was the first taken under the Commonwealth government with Census day on January 1. The Philippine population figure was 16,000,303.

1948 With the war just ended, a census was needed to plan for the reconstruction and rehabilitation of the country. The first census under the Republic of the Philippines was authorized by Republic Act No. 36, popularly known as the Census Act of 1946. Census day was on October 1, 1948. The population was counted at 19,234,182.

1960 The census for this year combined population and housing, the first of its kind to be undertaken. Conducted simultaneously with the census of population, the housing census included questions on housing conditions, area of farms operated, and the number of livestock and poultry raised. This provided the sampling frame for the agriculture census. The population counted was 27,087,685.

1970 Executive Order No. 149 designated Sunday, February 15, 1970, as Census Day. But this had to be reset to May 6 because of budgetary constraints. It was compensated, however, with a wider and more vigorous participation from government agencies and their instrumentalities. The total population was 36,684,486.

1975 The first mid-decade population census was undertaken in May of this year, almost three years after Martial Law was declared on September 21, 1972. The census, aptly referred to as the Integrated Census of Population and Its Economic Activities, was sanctioned by Presidential Decree No. 650. The Philippine population was registered at 42,070,660.

1980 The Census of Population for this period, together with the Census of Housing, commenced on May 1.

It was during this census year when Parliamentary Bill No. 809, filed in February 1980, proposed "to hold the census every 10 years beginning in 1980 without prejudice to the undertaking of special censuses on agriculture, industry, commerce, housing and other sectors as may be approved by the National Economic and Development Authority." The said bill was enacted as Batas Pambansa Bilang 72 one month after the 1980 census enumeration ended.

Proclamation No. 2170 declared as official the 1980 population count conducted by the National Census and Statistics Office. The population was counted at 48,098,460.

1990 The Census of Population and Housing (CPH) for this period was conducted in May 1990. For the first time, a Census logo and slogan contest was launched nationwide. The winning slogan was "Sensong Pambayan, Sandigan ng Kaunlaran."

Pursuant to the provision of Batas Pambansa Bilang 72, a final report on the total population, total household population, and number of households at the barangay level was approved by the President under Proclamation No. 688 dated February 12, 1991. The population reported was 60,703,206.

1995 More popularly known as the POPCEN, the 1995 Census of Population was undertaken in the month of September. The data gathered provided an updated basis for the apportionment of the Internal Revenue Allocation to local government units and for the creation of new legislative areas such as regions, provinces, municipalities and barangays.

Again, pursuant to Batas Pambansa Bilang 72, the population count and the number of households at the barangay level were declared official by the President under Proclamation No. 849 dated August 14, 1996. The total population was recorded at 68,616,536.

2000 The 2000 Census of Population and Housing or Census 2000 was conducted in May 2000. This is the 11th census of population conducted in the country since 1903, and the 5th census of housing conducted in the country since 1960. The data gathered will provide government planners, policy makers and administrators with data on which to base their social and economic development plans and program. The data gathered will also provide updated data on the size of the population that will serve as basis for the apportionment of congressional seats for the legislative branch; creation of new local government units, i.e., provinces, cities, municipalities and barangays; and conversion of a unit such as a municipality into a city.

Pursuant to Batas Pambansa Blg. 72, the results of Census 2000, i.e., the population count and the number of household were proclaimed and declared official by the President of the Philippine under Proclamation No. 28 dated April 18, 2001. The Philippines population as of May 1, 2000 was recorded at 76,498,735 persons.

source: 2000 Census and prior years