MANILA, Philippines -- The call center industry now employs no less than 200,000 workers and continues to grow by 30 percent every year, according to an official tally by industry group Call Center Association of the Philippines (CCAP).

CCAP has 39 member-companies consisting of the largest call center operators in the country. CCAP members alone account for about two-thirds of the 151,000-seat industry total.

This translates to a minimum of 200,000 workers, according to Raffy David, CCAP board director and head of its membership committee.

"Some in the industry said the total could be as much as 300,000 or more but as an industry group our conservative estimate is 200,000 workers," David said in an interview with INQUIRER.net.

Call center operators continue to expand operations in the Philippines, generating employment outside of business districts Makati and Mandaluyong City and into so-called "next-wave" cities.

Improved telecommunications infrastructure and a ready pool of English-speaking college graduates in these cities have attracted further investments from operators.

According to CCAP, 25 out of 39 member-companies have operations in 16 cities outside the Makati and Ortigas business districts. Quezon City, home to top-tier universities like the University of the Philippines and the Ateneo de Manila University, now have call center facilities in 14 locations.

CCAP also noted operators present in Cebu, Bacolod, Muntinlupa, Manila, Baguio, Laguna, Batangas, Taguig, Pasay, Paranaque, Marikina, Rizal Cavite, Angeles and Dumaguete.

Dan Reyes, CCAP director, said the industry is growing by 30 percent every year, both in terms of seat capacity and headcount.

The industry still largely caters to US-based customers although Reyes noted operators are attracting offshore clients from other markets like the UK, whose National Outsourcing Association (NOA) recently noted the Philippines as the best offshoring destination last year.

"There are now customers from Australia and even New Zealand being supported by call centers here," Reyes said. "The industry is now serving different time zones."