Brazil is seeing the lowest population of registered teen voters for the upcoming October election, according to reports.

La Terra cited a local newspaper reported that the number of voters has fallen by one-third since the last election and has reached numbers as low as 2002.

In Brazil, the legal age to vote is 18, but 16- and 17-year-olds are allowed to vote as well. And about 60 percent of young voters don't align with any political party. Mayoral elections have a higher voter turnout, about 43 percent, but state and national elections are less than that.

In previous years of national elections, 2002, 2006 and 2010, at least 35 percent of young voters turned out. The list for the October election is about 26 percent, La Terra reported. Protests last year appear to be responsible.

Millions of young voters -- teens and young adults -- took to the streets in June 2013 to protest corruption in the government, tax hikes and the then-upcoming cost of the soccer World Cup, according to BBC.

More than half of those protesting were younger than 25, and at least 84 percent backed no political party at the time.

"People are so disgusted with the system, so fed up that now we're demanding change," said Camila Sena, 18, last year to BBC.

Before that protest, the last big one in the country had been to impeach the president in 1992.

In addition to the decrease in young voters, it appears a number of those who are going to vote intend to vote blank. This is not uncommon but the percentage of voters polled who said they would do it has increased since 2010, according to Brasil247.

In 2010, about 10 percent of 440,000 said they would vote blank, but this year the number has reached 17 percent.