Seoul (CNN) When giving their age to foreigners, South Koreans typically say two numbers. Their "international age," or the number of years since they were born, and their "Korean age," which could be one -- or even two -- years higher.

In Korea, babies are considered a year old on the day they're born, meaning that someone born in January 1990 is 30 in Korea, not 29. For those born late in the year, the gap can be even greater. A baby born on December 31 turns two on January 1.

This can cause a great deal of confusion, which lawmaker Hwang Ju-hong is determined to change.

South Korea is the "only nation" in East Asia to still use the traditional system, Hwang said when he introduced a bill into parliament earlier this year to bring it in line with the international norm.

Confusing tradition

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