as a percentage. Also known as a Rating or T.A.R.P (Total Audience Rating Point). Audience share: The number of listeners (or viewers) for a given channel over a given time period, expressed as a percentage of the total audience potential for the total market. (The audience share is normally calculated by dividing a given channel's average audience by the average audience of all channels). Audience potential: The total number of people in a given geographical area who conform to a specific definition, such as the number of people with a television (or radio) set or the total number of people aged 6–12 years. Population potentials are normally derived from the census figures and are used to estimate the potential market reach. Audience movement by session: The number of listeners (or viewers) who switch channels during a given time period. Audience profile: Analysis of audience by selected demographic, psychographic or behavioural variables. Cumulative audience (CUME): The number of different listeners (or viewers) in a given time period; also known as reach. People Using Television (PUT): The number of people (or households) tuned to any channel during a given time period. Out-of-home media Opportunities to see (OTS) – a crude measure of the number of people who were exposed to the medium, For example, the number of cars that drive past an outdoor billboard in a given time period Internet and digital media Site traffic: The number of visitors to a website within a given time period (e.g. a month) Unique visitors: The number of different visitors to a website within a given time period Site stickiness: The average length of time a person remains on a page (a measure of audience engagement) Average page views per visit: The number of different pages generated by a visitor to a site (a measure of engagement) Click through rate (CTR): The number of people who clicked on an advertisement or advertising link Cost per click (CPS): The average cost of generating one click through Rate of return visitors: The number of unique visitors who return to a site Bounce rate: Number of site visitors who leave the site within a predetermined time (seconds) Although much of the audience research data is only available to subscribers and prospective advertisers, basic information is published for the general public, often as topline survey findings. The type and depth of freely available information varies across geographic markets. The