My lunch bill got stranger by the day.

Every year, I come to the same Malaysian paradise. Time magazine once rated it one of the 10 most beautiful islands in the world.

In 2015, it was better than ever because it just kept getting cheaper. The fresh curried fish, pizza, fruit smoothie and coconut that I had for lunch cost just $7.

That’s when I pulled out my laptop. I checked the U.S. dollar against global currencies. The greenback was a rocket beside a bunch of balloons.

Last year, it gained more than 21 percent over Malaysia’s ringgit. Over the past 36 months, it gained 43 percent. (U.S. Dollar Rises Against Malaysian Ringgit 2013-2016. Source: OANDA Historical exchange rates)

I pushed my coconut aside and started to write, Think Like Warren Buffett While Vacationing Abroad. For American travelers, the world was on sale.

But there was a benefit for those whose currencies took a whooping. Perhaps they couldn’t enjoy a cheap trip to Disneyland. But if they bought U.S. stocks they hitched a ride on the dollar.

With U.S. exposure, they fared quite well.

American investors can’t say the same. Vanguard’s S&P 500 Index Fund mostly climbed from January to July.

But it fell hard in August. By year-end it had gained a paltry 1.24 percent.