WP34s - Sort sum registers to calculate percentile

[Marko]

In my first attempts to do some programming in my WP34s, I stumbled upon this wikipedia article on the calculation of percentiles. In the section about The Linear Interpolation Between Closest Ranks method it says: "In particular, given the N sorted values, we define the percent rank corresponding to the nth value as ... [forumula]"
Can the values in the Sum registers be sorted using R-SORT? And if not, what is a better way to achieve this? Any help in the right direction is thankfully appreciated.