How Gatling computes percentile values ?

I ran a small test in gatling and made 10 requests overall.
Here are the response time distribution of these 10 requests in mili seconds,

34
38
38
41
41
42
44
53
70
900

Attached is the gatling report with the response time metrics,

Can you please provide the calculation used to compute the 95th and 99th percentile ? They look wrong to me.

https://github.com/tdunning/t-digest