Show Hide image 29 June 2012 Piers Morgan's CNN show receives lowest ratings in 21 years Loss of target audience despite prime time slot. Piers Morgan’s American talk show has brought in the lowest viewer ratings recorded on the CNN prime time slot in 21 years. Morgan took over the 9pm slot from Larry King in January 2011, launching the show with a huge advertising campaign. The debut show received an audience of 2.1m viewers, which has since fallen by 25 per cent. More worrying for the UK television personality, the key audience of 25 to 54 year olds has fallen further. Having received an initial audience of 521,000 viewers, Morgan was watched by only 39,000 25-54 year olds in May, down 32 percent. The show has hosted popular guests, with celebrities including Charlie Sheen and Glee's Jane Lynch, and political figures including the Dalai Lama. Morgan's shown runs for 60-minutes in a prime time slot. By Helen Robb Helen Robb reads PPE at Oxford University where she is deputy editor of ISIS magazine.