Mega Manila, as a loose metropolitan area defined by the Philippine Information Agency (PIA), is divided into the national capital region (Metro Manila) and the suburbs of regions 3 (Central Luzon) and 4 (Calabarzon and Mimaropa). Mega Manila's 2010 population is projected at 35,607,000, or 37.8% of the country's population, and covers roughly half of Luzon, about 50,000 square kilometers, including many rural areas.
Non-continuously-built-up areas scattered in this defined region occupy in total less than a third of the regional land area, and have a negligible population. This area has a higher ownership of televisions per household anywhere in the country due to its relative economic prosperity as compared to other areas in the country. Radio ratings agency Radio Research Council (provided by KBP) also provide measurement of audience ratings.
Continuous suburban sprawl, as can be seen from a clear night sky on an plane, would be closest to the TV ratings' definition but some of the sprawl would also be in Batangas. Including this province would push the population (using above source) to about 27.3 million including some non built-up or non-continuously built-up areas.