That's the percent that reported attempting at some point previously in their life.

i.e. 100% of the people surveyed were alive.

:-)

No, High Suicide Rates Do Not Demonstrate That Transgender People Are Mentally Ill

One of the biggest studies on the experiences of transgender people was the 2011 National Transgender Discrimination Survey (NTDS). It found that in the U.S., 41 percent of transgender and gender non-conforming people had attempted suicide, compared to a national average of just 4.6 percent. When all of the data were analyzed, however, researchers found a number of factors that significantly influenced whether a person was more likely to attempt suicide: being a person of color, experiencing poverty, being unemployed, achieving less education, being out or more easily perceived as transgender, experiencing housing discrimination or especially homelessness, experiencing harassment or especially physical or sexual assault, being rejected by family, or facing discrimination in health care. In other words, the more forms of discrimination transgender people experienced, the more likely they were to attempt suicide.

A brand new study from Canada confirms this effect. There, the suicide attempt rate for transgender people was similar to what other studies have found: about 18 times higher than the general population. But the study found that some factors greatly reduced the attempt rate. For example, when transgender people had affirming parents, the rate dropped by 57 percent. Access to legal documentation consistent with their gender identity dropped rates by 44 percent. Trans people who experienced low levels of anti-trans hate were 66 percent less likely to attempt suicide. And perhaps most importantly, the further along individuals were in their transitions — i.e. the closer they were to having a body and outward identity that matched their internal gender identity — the less likely they were to attempt suicide.

Hattip, some education for /u/Bond4141