BARB is the industry standard television audience measurement service for broadcasters and advertising companies in the UK. It provides data on viewership numbers that TV channels can use to show advertising companies how many potential viewers their ads may reach during or around popular shows. Some of the highest viewed crime drama and mystery shows according to BARB data are Death Comes To Pemberley with 7.81 million views, Agatha Christie's Marple with 4.57 million views, and Midsomer Murders with 4.45 million views. These shows likely target older audiences as younger viewers may find the crime plots and storylines difficult to understand.