When displaying your ping in-game do the acronyms mean?

It shows FPS, TMP, PNG, RTT and IND. FPS, TMP and PNG are self explanatory but I'm not sure what RTT and IND ms is. Reason I'm asking is that my IND ms seems to be really shaky these past 2 days to the point where I can't really play the game but my PNG is fine.

Thanks in advance for the help.