"Concerns were raised about the issue."
So, during the Blair/Brown governments, 1997 - 2010, 408 peerages were created, of which 173 were Labour = 42%.
During the Cameron/Clegg coalition government, 2010 - 2015, 117 peerages were created of which 71 were Conservative or Lib Dem = 61%.
It seems that the party/parties involved in government gives/give the lion's share of peerages to its/their own supporters.
Surprise, surprise! However, it appears that the lion's share is sometimes half as large again under some parties as it is under others! Time these concerns were addressed!