SEOUL • Mr Park Jae Yeol should have retired 11 years ago. But, unable to survive on meagre South Korean state pensions, the 71-year-old is obliged to continue working, delivering packages to high-rise apartments.
He pushes a cartload of brown boxes into a lift at a block of flats in Seoul, his ageing eyes strained by constant squinting at tiny address labels. "Money is the biggest reason" for continuing to work, he said.
He is one of the millions of elderly South Koreans pushed into labour well past the official retirement age of 60. Social safety nets in the rapidly ageing country are weak, despite South Korea ranking in the OECD club of developed countries.
More than 45 per cent of elderly South Koreans live in relative poverty - defined as surviving on less than half of the median household income - by far the highest proportion in the Organisation for Economic Cooperation and Development (OECD), where the average is 12.5 per cent.
Mr Park is also one of the millions whose efforts powered the "Miracle on the Han", the country's transformation from a war-ravaged ruin in the 1950s to the world's 11th-largest economy.
A high school graduate, he worked in air-conditioning maintenance, earning enough to raise three children and buy an apartment in Seoul. He set up his own air-conditioning servicing company, but, like many people his age, was never able to build up a cushion of savings for his twilight years.
Elderly South Koreans living in relative poverty - defined as surviving on less than half of the median household income.
Average proportion of elderly living in relative poverty in the OECD.
"Our generation was too busy just trying to survive and raise children during these crazy times, unable to prepare for our post-retirement years," Mr Park said.
South Korea introduced a national pension scheme only in 1988 and it did not become mandatory until 1999. Payouts are dependent on the amount and duration of contributions, with a 10-year minimum.
Researcher Hwang Nam Hui at the Korea Institute for Health and Social Affairs said "many of those in their 70s and 80s missed a chance to pay into the system, so are left out of pension benefits" and must survive on welfare payments that are "ludicrously low".
Mr Park's firm went bankrupt in 2012, resulting in his having to rely on a national pension of about US$130 (S$174) a month and an elderly subsidy of around US$180 - "nowhere near enough" to live on in one of the world's most expensive cities. "That's not even enough for pocket money," he said.
So he signed up for a state programme which helps the elderly get menial jobs, and started working as a deliveryman in 2014. He now works three days a week, taking up to 100 packages to their destinations and earning about US$500 a month.
Most of his co-workers are in their 70s, with the oldest 78.
Mr Park has already worked for more than five decades, but said he hopes to carry on "as long as my health allows... maybe until I'm 80".
South Korea's fertility rate - the average number of babies women have in their lifetime - hit a record low of 1.05 last year, far below the replacement rate of 2.1. Over-65s are expected to make up 25 per cent of the population by 2030 - a phenomenon dubbed the "silver tsunami".
In the past, traditional extended family structures, with three generations living under one roof, ensured the elderly a life of relative comfort with support from their offspring, researcher Hwang said.
But the radical social changes of recent decades have seen filial obligations wane, and the elderly forced to work to support themselves.
Statistics released in March showed that more South Koreans in their 60s were economically active - either employed or seeking a job - than those in their 20s.
Mr Park and his 63-year-old wife - who works as a convenience store cashier - take only one week off a year, to go to the resort island of Jeju. But, he insists: "I feel so grateful and lucky to still be able to work."