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Since their retirement in 2015, Kristy Shen, 36, and Bryce Leung, 37, have been traveling around the world. Initially, the millennial couple from Toronto wanted to travel for only one year, but it's been four years and they've not stopped yet.

Leung and his partner found out that after a year of traveling around the world, it cost about the same as living in one location such as in a pricey city like New York.

Shen and Leung are supporters of the "Financial Independence Retire Early," or FIRE Movement. The movement's supporters spend years saving and investing their money before more traditional retirement age and quit their jobs.

The couple also runs the Millennial Revolution blog, and recently authored a book called "Quit Like a Millionaire."

Before they began to follow the FIRE movement, Shen said that her goal was to do the thing everyone else does like buy a house, work until you're 65 years old, and retire with a pension. Houses in Toronto, however, were over $1 million and Shen noticed that her job as a computer engineer was becoming less stable as positions were outsourced to places such as India.

Leung said that he began to look at what else they could do with their money. About half a million dollars at that point, he found that it would be possible to achieve financial independence by investing the money in low-cost index funds. Leung ran the math and realized that even just assuming pretty conservative rates of return in the stock market they could either buy a house or start doing this other thing, which is traveling.

Shen and Leung began to focus on saving and investing their money around 2012. As Leung had predicted, they had to retire from their jobs for 3 years - in addition to the previous 6 years they had worked, without focusing on FIRE.

They traveled around the world for a year once they finally retired, thinking they'd move back to North America and live in a cheap city. But it turned out they love to continue the travels.

One example, he said, is that they were living off about $40,000 a year when they lived in Canada. But when they moved to Thailand, their living costs dropped substantially.

Leung and Shen have found that retirement has made their lives healthier and more fulfilling besides being able to travel constantly.

Shen and Leung currently run an investment workshop on their blog that is free of charge to allow anyone to access it. Even though they are still traveling around the world since they started in 2015, their strategy has changed.

Shen added that the world has become one city and they are kind of visiting different communities like the ex-pat community or FIRE groups in a particular country. She described it as more like a nomadic lifestyle. Shen and Leung don't think they'll ever want to stop this lifestyle. She explained that it is more like you've gone out of the matrix, and can't really go back in.

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