Which RGA analysis to use?

[Robbie]

I have operational data from multiple (similar) repairable systems over a 10 year period that I want to analyse. I've started by using both the fielded systems options (repairable and fleet), but don't quite undertsand how to make the interpretation of results. The user manual (p34) refers to figure 3.13 which has three systems - isn't the three systems then a fleet? Whats the difference between system and fleet - and why when I enter the data in (say) fleet format, analyse it and transfer to repairable system format, the output is different, shouldn't it be ore or less the same?