And that's about what I'd expect with Rodinal in normal development.
Now let me tell you how I have gotten the full box speed back in (Pa)Rodinal: I develop at 1:50, but I extend the development time (IIRC, about double "normal"), and I agitate only two gentle inversions every third minute. Development times run up to 20 minutes, but you get Rodinal character (acutance, crisp grain) and recover most or all of the 1/3 to 2/3 stop of speed loss Rodinal would normally give.
Edit: I was going to paste in the times I used to use with a couple example films (haven't used Parodinal in a while, I should probably mix up a batch), but apparently, I can't use the Wayback Machine from my work network because it isn't https compliant.