Mmmmmm I'll spell it out for you......
December 2011 - 98.9 (2011 average = 99.3)
December 2012 - 100.9, (2012 average = 100)
that's not an 8.2% rise
And the graph I showed (nationwide) showed clearly falling rents across the nation in 2012, Dublin rises in 2012 negated these on the overall figures)
One has to look beyond the headlines when talking about specifics
The 2012 average of 100 seems the be the starting point ......... that does indeed indicate that the 8.2% rise wasn't seen in 2012, if it was then they'd have taken 2011 as the starting point, but it wasn't so they couldn't. HTH.
2009 to 2012 (inclusive) was the bottom of the rental market. As per your screenshot. You won't find a 2012 report bleating on about rising rents, nationwide.