Statistics without context

My husband and I watch this series together.
I noticed in this most recent installment (Gaycation in the US)
there was a statistic sited that the longevity of black-trans-females was 35 years.
I found myself a bit at sea hearing this.
Does that mean over all longevity (from birth)? Or from the time they are known as a trans-person?
The other question I had (even though the emphasis was on the violence sustained in to members of this community) was is this statistic soley based on violence occuring toward black-trans-females...or does that include other attributes, such as health issues due to transition medical care etc.?
Thank you for reading.
Gypsyohara in Fl.