More than 21 million domestic and international tourists visited Houston in 2017 according to a new report, marking a 6 percent increase in domestic tourism from 2016.

It also marks a major step towards reaching the city's benchmark goal of 25 million visits by 2020.

The report, compiled by OmniTrak's TravelTrakAmerica and Travel Marketing Insights, found that millennials led domestic tourism numbers. Of the 18.3 million domestic visits, 80 percent were overnight visits and 20 percent came for day trips.

About 73 percent of domestic tourists came for leisure activities with 15 percent here for business.

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The estimated 3.5 million international visits represented a 3.5 percent increase from 2016. Though preliminary national figures show a 9 percent decline in travel from Mexico to the U.S., there was a 1.5 percent increase in the number of Mexican tourists visiting Houston from 2016.

Factors driving the overall growth included Super Bowl LI, the World Series, and focused marketing efforts like the HolaHouston campaign that attracted Mexican tourists in particular.

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"We have bounced back from Harvey, but it is the diverse and welcoming nature of this city that shines brightly across the country and now draws visitors in increasing numbers," said Mayor Sylvester Turner in a statement.

Annual nights booked for future conventions rose to 802,859 in 2017, representing a 5 percent increase over 2016. and traffic to the VisitHouston.com collection of websites rose to 7.4 million, representing a 9% increase over 2016.

The mayor added that the tourism industry supports more than 140,000 jobs in the Houston region, contributing $16.5 billion to the local economy.