LLZME,
I guess I should clarify..Jepp uses State data to build their charts.
They use the data available and put that into their database, and they use their database to create the charts and navdatabase. This is the same for the other providers.
When I said they dont derive anything, I guess I did oversimplify, as I was speaking about the altitude of the DME itself. Sorry about that.
They do interpolate, and of course, Jepp designs procedures.
I have been involved with multiple providers and the State source, and frequently find differences, some very significant.
Reynolds, in the final approach segment, typically, the ROC tapers from 200' feet to 500' at the FAF.