Charts can seem dull. But not to data scientist Tariq Khokhar at the World Bank. When he looked through a year's worth of charts, graphs, maps and more, he was excited by the numbers.

For example, although the world's population has increased by 2 billion people since 1990, there are 1.1 billion fewer people living in extreme poverty, under $1.90 a day (highlighted in blue in the chart below). "I'm amazed at the progress," Khokhar says.

In December, he worked with his colleagues to identify what he calls the 12 most "popular and interesting" World Bank charts of 2016, which he highlighted in a blog post on the Bank's website.

The graphs, which range from how many people live without toilets to where the world's youngest people live, reveal a few intriguing challenges our planet will face in the next few decades.

Here's a sampling of the charts that caught his eye.

Who's Smoking?

In the majority of countries, smoking rates have gone down in the past 15 years. But for 20 mostly low- and middle-income countries, they've gone up. According to the World Health Organization, tobacco smoking kills around 6 million people a year — and nearly 80 percent of the world's 1 billion smokers come from the developing world. Not only is it a health issue, it's an economic one. Tobacco-related illness or death deprives families of income — imagine if the breadwinner of a family gets sick and can't work — and raises the cost of health care.

Phone Phenomenon

In 2000, just 4 percent of the 5 billion people living in low- and middle-income countries had access to a mobile phone. In 2015, that number skyrocketed to 94 percent of the 6 billion people in that population — making it easier to find someone who might lend you their mobile phone than finding clean water or electricity.

While a 2016 study from the World Bank says that mobile phones have boosted growth and expanded opportunities for some in the developing world (through apps that provide health care information or make mobile payments) not everyone benefits. Only about a third of the people who have access to a mobile phone have access to the Internet, which is necessary to use many of these mobile innovations.

Jobless Youth

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