According to the new report from The Group, increasing numbers of people are seeking information from FTSE100 companies via social media, but while many companies have invested in social media communications, a significant proportion have yet to respond adequately.

Carnival ranks highest in the index and was found to have a strong presence across all channels measured and topped the rankings for corporate blogging. The report notes, however, that despite having the best overall set of social media channels, the company did not make the most effective use of these resources during the recent Costa Concordia incident. Burberry, which came second in the Index and benefits from having a shared corporate and consumer brand name, leads the field across Facebook, Twitter and YouTube.

The number of Facebook fans has risen significantly to more than 14 million fans overall. However demand for information from Facebook could be outstripping supply, with a decrease in the number of companies adopting Facebook Pages and only 39 FTSE100 companies running an account.

By comparison, 53 companies have an active YouTube channel, up from 44 in June 2011, and 61 companies have an active Twitter channel, although 42 of those do not respond to direct queries which suggest it is being used as a broadcast tool rather than to encourage dialogue.