Audience: the average number of individuals watching a TV channel in a given timeframe.- Audience measurement systems provide estimates for TV audiences on a minute-by-minute basis. The data gathered can be summarised as an average for a time slot, an individual piece of content or a longer period as required.
- Syndicated research surveys provide estimated audiences for hourly time slots and total viewers per day, per week, per month and per year.
Target audience: a group of individuals, usually defined by their economic, social or behavioural characteristics, to whom an advertisement or piece of content is aimed.
Profile: the percentage of the target audience compared to the total audience. - Calculation: audience of the target group / audience of all individuals.
- e.g., if Channel A has a total daily audience of one million people and 350,000 fit into a target audience demanded by a brief, then 35% of the audience are said to fit into the target profile
Share: the percentage of the audience watching one particular TV channel compared to the total number of people watching TV in the same period.
- Calculation: a specific TV channel’s audience ÷ total TV audience
- e.g. if Channel A has an average audience of one million people in a particular time slot and an average of five million people were watching TV in that time slot, then Channel A would be said to have a share of 20%
Reach: the number of individuals exposed to a piece of content or an advertising message. These individuals may be exposed to an advertisement through one or more TV channels or media in a particular period of time. - This figure is unduplicated, which means that a person exposed to a campaign once on a TV channel is counted as one individual reached by that campaign. Someone who sees the campaign twice on different TV channels and once on a website is also counted as one individual reached by that campaign, even though they have been exposed to the campaign three times (see impacts below).
- Reach can be expressed in raw numbers (e.g. the campaign reached 3 million business travellers) or in percentage/profile terms (the campaign reached 35% of all business travellers).
Impacts: the number of times an individual is exposed to an advertising campaign.- This figure is duplicated, which means that the number of impacts may exceed the total reach of a campaign.
- e.g., the advertising campaign had a total reach of 3 million people. All of these people saw an ad twice, resulting in 6 million impacts.
Frequency: the ratio between reach and impacts, i.e. the average number of times a viewer was exposed to an ad campaign. - An individual may be exposed to a campaign twice – a frequency of 2.
- We can also refer to the average frequency of an audience or a target audience. If a campaign reaches 2 million people and between them they see it 3 million times, the average frequency would be 1.5. This means that on average each viewer was exposed to the campaign 1.5 times, even though many would be exposed just once and others may be exposed two or more times.
CPT (Cost Per Thousand, also known as CPM): the cost of reaching 1,000 people in a target audience. This can be used as a rate on which to purchase TV advertising. It may also be used to demonstrate the relative cost of a campaign on one channel compared to another. - Calculation: (average cost per spot / average target audience) x 1,000.
- e.g. a spot costs €5,000 to run and the estimated audience at a given time is 500 thousand people:
- €5,000 ÷ 500,000) = €0.01
- €0.01 is multiplied x 1,000 to give our cost per thousand
- = €10.
- Alternative calculation: campaign budget ÷ (campaign impacts ÷ 1,000)
- e.g. the campaign budget is €20,000 and the campaign is seen 1 million times:
- €20,000 ÷ (1,000,000 ÷ 1,000)
- = €20,000 ÷ 1,000
- = €20.
GRP (gross ratings point): GRPs are used to measure the potential strength of an advertising campaign. To calculate GRPs, the number of impacts of an advertising campaign is compared with the number of people in the target audience. - GRPs are expressed as a percentage of the target population, but because they are based on impacts rather than reach, the number can be more than 100.
- Calculation: GRP = (impacts ÷ size of target audience) x 100
- e.g., an advertising campaign targeting Europe’s 100,000 frequent business travellers is run on Channel A and is seen 200,000 times over the course of the campaign
- Therefore (200,000 ÷ 100,000) = 2
- 2 is multiplied by 100 to give a percentage: 2 x 100 = 200 GRPs
- Alternative calculation: GRP = reach in % x frequency
- e.g., an ad is broadcast twice on Channel A between 12.00 and 14.00 CET and it is estimated that 20% of business travellers are watching in this time period
- Therefore 20 x 2 = 40 GRPs
- Cost per GRP, i.e. the cost to pay for 1 GRP to reach 1% of the target group.
Estimated Reach & Frequency: a report provided to an advertiser in advance (or after transmission) of an advertising campaign. It contains many of the above measures for the total audience and any target audiences, including Reach, Impacts Frequency, CPT, GRPs, cost per GRP, etc.
Visit: A session of activity undertaken by a person on a website. Measures are undertaken by web analytics software to ensure that automated traffic from other sources is not counted.
Unique visitor (or ‘unique user’): in web analytics, the number of individuals who visit a website at least once in a defined period of time. - In reality this also applies to individual devices, such as separate work and home computers, or mobiles. Each of these would likely have identifiers, such as a different IP address or a cookie, which would mark them as different.
- If someone visits twenty pages within a website in the defined period, the server will only count one unique visitor
A reporting period may be a few days or several months, so the number of unique visitors will vary depending on the period used.
Page view: recorded when a user requests to load an HTML file (generally a web page).
Ad impression: used to measure when an ad has been displayed on a website.
CPT or CPM (Cost per mille – ‘mille’ means ‘thousand’): The cost to an advertiser for each set of a thousand ad impressions. This is equivalent to ‘impacts’ for TV.
Click-through rate (CTR): how many people are actively responding to ads, generally by clicking on them, compared to the number of ad impressions delivered.
Cost per click (CPC): how much advertising costs based on the number of clicks compared to the total ad impressions delivered.
