A new study shows that there are over ten million Americans that openly identify as LGBT. The survey, done by Gallup, shows that the percentage of openly LGBT Americans has increased since the survey was first conducted in 2012—3.5% to 4.1%. Study reveals there are now over 10 million Americans who identify as LGBT.

“These figures, drawn from the largest representative sample of LGBT Americans collected in the U.S., imply that more than an estimated 10 million adults now identify as LGBT in the U.S. today, approximately 1.75 million more compared with 2012,” Gallup wrote in a statement.

A simple random survey about sexuality, though, is difficult to get accurate numbers, especially when calculating a total population. Many are uncomfortable openly discussing their sexuality, especially over the phone (how this survey was conducted).

The increase in the last few years is most likely due to Millennials. Millennials make up a total of 32% of the general adult population and accounted for 43% of all LGBT Americans.