THE number of people in the UK who have listened to the radio via the internet has increased by 2.5 million in six months, figures out today showed.

And six million people have downloaded a podcast, with podcasting seen as having a positive effect on radio listening.

Rajar (Radio Joint Audience Research Ltd) released findings of its second survey into podcasting and radio listening via the internet.

The latest survey was conducted during April and May 2008 by Ipsos Mori and followed the previous online survey conducted in October and November 2007.

The findings were based on 863 respondents who were asked to complete an online questionnaire.

People were asked if they had ever listened to the radio via the internet and found that 14.5 million people had done so - up 2.5 million from 12 million in November 2007.

The average user of "listen again" services listened to 1.8 programmes each week.

Three quarters of those listeners said the service had no impact on the amount of live radio to which they listened.

And almost half said they were listening to radio programmes to which they did not listen previously.

Rajar research manager Christel Lacaze said: "Now in its second instalment, this survey gives a unique insight into the behaviour of the online/offline audio community and the impact of new audio delivery formats on traditional live radio listening.

"It also provides perspective on the relative impact of each of these activities."

Six million people have downloaded a podcast, up from 4.3 million in the previous survey.

iTunes remained the software of choice, used by almost three-quarters of podcast users to subscribe to podcasts.

Podcasting appeared to have a marginally positive effect on live radio listening.

Almost 15% of respondents said they listened to more live radio since they began downloading podcasts while 10% stated they listened to less and 39% said they were listening to radio programmes they did not listen to previously.

Podcast listening occurred throughout the day, with an evening peak, when 44% of podcast users pressed the play button.

The survey found that 53% of respondents said they would be interested in downloading podcasts containing advertising if they were free, while only 31% responded positively to the idea of podcasts without adverts that had to be paid for.