Well, like I said ... not really very important as circumstances differ for almost everyone. Here's my example to show how difficult it is to make any sense of what the "average" is.
I flew gliders before power, so obviously knew the basics before I ever flew powered aircraft. My times were ... 3.5 hrs from zero to first glider solo (34 landings). Then 9 hours to go solo in a DH82a Tigermoth, having gained 19 hours, (200 landings) in gliders and a bronze C. I took my skills test at 35 hours, but my qualifying cross country was delayed by three months due weather then lack of money. I completed my PPL with 43 hours, exactly two years after my first powered flight.
The gliding was a good grounding and as you can see, you certainly get to practise landings! You might clock more hours in gliders these days as they are more efficient (my average training flight was about 4 minutes!) but the older gliders were great for learning quickly.
I might have gone solo faster if the training had been more consistant or in an "easier" type than a Tigermoth. Then again, I may have taken longer if I'd not flown gliders first or been older, or caught bad weather, or had an instructor I clashed with, or, or, or ....
See what I mean? It's almost pointless to try and compare oneself to the "average".
SS