Harvard professor Dr. Jeffrey Williamson talked to Business Nightly on Wednesday to talk about emigration trends.

He said that every emigrant-sending country has gone through the following stages: rising, leveling, then descending. "I don't expect Philippines to be any different," he said during the interview.

Key driving forces for the eventual easing off include demography and improving job choices at home.

He explained that as young adults emigrate, the number of young adults at home as a share of the population will be less. "The exit rate will tend to ease off," he said.

For countries that are growing rapidly, the "economic distance" difference between the good jobs abroad and at home shrink. "There are less incentives to move," he explained.

While the Philippines has generally been unable to provide enough good jobs to keep Filipinos from seeking greener pastures at home, Williamson stressed that things go slowly. From the surge of emigration from the Philippines, Mexico, India, and others in the 1970's, he said the downside may come in the next 30 to 40 years.

"It won't happen in the next 5 or 10 years, but it will be a part of your life in the next 30 (years)," he said.

He also touched on remittances, and how these are dependent on factors beyond the control of the Philippines.

"Although you get a return to the migration [through] remittances, and those who leave have a better advantage of improving their condition, but those remittances and the ability to get those jobs abroad are determined by policies ion those countries. If you are exporting something else, it will be dependent on conditions at home. That is one of the weaknesses of relying on remittances," he stressed.

Business Nightly airs on ANC at 9 pm weeknights.