Today, the President tweeted that he is barring all transgender individuals from serving in the military "in any capacity." One justification he claimed was their "tremendous medical costs." But, as STAT points out, "at least two studies in recent years have found that the cost of medical care for transgender service members would be minimal."

A June 2016 study from the RAND Corporation estimated that there were between 1,320 and 6,630 transgender active-duty service members — out of 1.3 million service members in total — and noted that not all of them would seek treatment related to gender transitioning. The study also estimated that the cost associated with medical care for gender transition would only increase military health care expenditures by between $2.4 million and $8.4 million each year — an increase of between 0.04 and 0.13 percent.

A September 2015 study published in the New England Journal of Medicine reached similar cost estimates. The study estimated that there were about 12,800 transgender service members who would be eligible for medical care. But it hypothesized that fewer than 200 would require care for gender transition each year, based on the percentage of transgender people who sought such care outside the military and the percentage of Australian service members who sought transition-related care.

The overall estimated cost to the Pentagon: $4.2 million to $5.6 million — what the study’s author called “little more than a rounding error in the military’s $47.8 billion annual health care budget.”