2015 has been another good year for Atresmedia. Helped by the economic upturn and despite the challenges that we are constantly facing, once again this year we demonstrated the strength of our position in the market, the power of our way of understanding the business and our ability to generate value. In the most difficult times we rightly laid some strong foundations that are allowing us, now that the recovery is in evidence, to boost our growth and face the future with optimism.
We have a product that is both recognised and recognisable thanks to its quality and attributes, one that is commercially attractive and scarce because very few are in a position to offer the market a multi-format product that is this broad, powerful and comprehensive. All of this is part of a global plan based on diversity as a differentiating value, a plan that makes our Group unique in the sector. This strategic vision is possibly one of the greatest legacies left to us by José Manuel Lara Bosch.
The success of the merger between Antena 3 and laSexta is undeniable and has shown that our decision was the correct one. The channel has integrated perfectly into our model and has made us better than ever. This can be seen from the response of the industry and audiences, as well as from the profitability ratios.
In the most difficult times we rightly laid some strong foundations that are allowing us, now that the recovery is in evidence, to boost our growth and face the future with optimismOur Group, in its commitment to diversity, is the one that best reflects what is actually happening in Spanish society. We understand the importance of our role in the system of checks and balances necessary for democratic life. We know that the better and more diverse the information received by the public, the better founded will be their decisions. In times such as those that we are experiencing now, this certainty only becomes stronger. The facts demonstrate that we are right: 2015 was the year in which Atresmedia established itself as the leading source of news for the Spanish people, who turned to us to learn about the major news and election events. 7d: el debate decisivo, broadcast simultaneously by Antena 3 and its international signal, laSexta, Onda Cero and streamed live through Atresplayer, attracted almost 10 million viewers and 48% of the audience. It was the culmination of this strategic focus on diversity and a group initiative of which we can feel very proud.
The advertising market has been positive for the second year running, underlining the fact that we are clearly on the path to recovery. As a result of the strong performance of all our business areas and our effective commercial policy, among other factors, the Atresmedia group has managed to take advantage of this improved advertising investment and has increased its net revenue by 9.8%, higher than the overall market growth rate, to stand at €970.2 million.
The success of the merger between Antena 3 and laSexta is undeniable and has shown that our decision was the correct one. The channel has integrated perfectly into our model and has made us better than everWith a management model that seeks efficiency and maximum profitability, the Company's gross operating profit stood at €165.7 million, achieving a sales margin of 17.1%; and the net profit was €99.2 million, double (+112.4%) that achieved in 2014.
By business area, Atresmedia Televisión has again improved its position, both qualitatively and quantitatively, which has led to an increase in net income of 9.2% compared to 2014. It is important to highlight the excellent work of Atresmedia Publicidad in the sale of our advertising spaces. With a customer-oriented approach and following the principles of innovation, efficiency and profitability, it has positioned itself as the largest seller of multimedia advertising space in the Spanish market, with a 19.3% share of the total investment in conventional media, and the highest rated in the sector in terms of the quality of the commercial service.
In 2015, Atresmedia Televisión had an average audience share of 26.8% and this figure rose to 27.7% during prime time, the slot with the most viewers, which allowed it to achieve a share of 42.1% of the total investment in television, showing significant annual growth (+0.6%).
Antena 3 (91%) and laSexta (56%) were again the channels with the greatest success rates for their new releases, most of them during prime time, the time slot with the higher consumption, where together the two channels were the most viewed in 2015, with 21.9%. This leadership was also extended to the commercial target (24.3%), that most demanded by the advertisers.
Antena 3, moreover, was again the leading channel during prime time in the commercial target with 14.9%, and was absolute leader during the afternoon (12.4%) and at weekends (13%). laSexta has continued to grow every month since the merger and achieved its best year so far with a 7.4% audience share, establishing itself as the country's third private channel. It also obtained its best ever prime time figure: 8.5%, which is 2.1% more than its direct competitor.
As I have already mentioned, in 2015 Atresmedia Televisión also added two new channels and did so successfully. These are MEGA, which became the themed channel with the strongest start in the history of DTT, with 2.1%, and Atreseries, which is achieving excellent audience figures despite not having complete coverage as the penetration of HD television is still insufficient. These channels are in addition to established brands like Neox and Nova, which have equalled their second best annual figures with 2.6% and 2.4% respectively.
Atresmedia Radio has had a historic year with its second best profitability rate, obtaining an EBITDA margin of 24.3%2015 has also been a good year for Atresmedia Radio. Suffice it to say that our Radio Division has had a historic year with its second best profitability rate, obtaining an EBITDA margin of 24.3%. This figure was produced in the context of the renovation of Onda Cero's morning slot. These events have again tested our ability to tackle challenges and, as we have done before, resolve them successfully. If Onda Cero has demonstrated anything during its 25 years, which it has been celebrating recently, it is its strength as a brand and its great ability to overcome problems and continue to grow. Supported by the strength of the Group, taking advantage of the inexhaustible pool of talent that is our Radio product and with the confidence of having the best professionals in the sector, I am convinced that the transition process, which is always the result of any change, will lead, sooner rather than later, to a new momentum and the meeting of the ambitious targets we have set ourselves.
In 2015, the channels Atresmedia Radio, Onda Cero, Melodía FM and Europa FM together achieved an average audience of almost five million listeners. As a result of these impressive figures, its position as an opinion leader for listeners and its good commercial strategy, the Division's net income grew above the market rate to stand at €89.9 million, representing growth of 10.6%. The gross operating profit amounted to €21.8 million (+24.2%), compared to €17.6 million in 2014.
The world of multimedia, which I have already mentioned, is a clear focus for the Group and forms part of our DNAThe world of multimedia, which I have already mentioned, is a clear focus for the Group and forms part of our DNA. For a long time now we have seen the reward for this commitment in our results. The Atresmedia Digital figures led to us closing the year as the Internet's leading audiovisual group, a trend that has been confirmed during the first few months of 2016. Atresmedia closed 2015 with more than 10.6 million unique users in December, according to the figures from comScore. In addition, with the launch of Flooxer, the new on-line platform for high quality short videos, we have taken another step in the group's multi-platform strategy.
Two years ago we decided to launch the Diversificación Division, a new business area designed to seek alternative sources of income away from our traditional business, therefore leaving us less exposed to downward cycles in the advertising market. Over these two years, thanks to hard work and a lot of creativity, the Diversificación team has managed to make the most of our licensed products and we have taken a very important step in our internationalisation strategy: through the channels Antena 3, Atreseries and ¡HOLA! TV, we are the European commercial operator with the most subscribed households (32 million) outside our borders. It is also worth mentioning that Atresmedia has managed to secure a very strong position in the Spanish entrepreneurial ecosystem, participating in ten high potential start-ups through the media for equity model.
In 2015 we have set an important milestone in our international strategy: through the channels Antena 3, Atreseries and ¡HOLA! TV, we are the European commercial operator with the most subscribed households (32 million) outside our bordersAnother of the areas that has experienced most growth is Atresmedia Cine. The Group's Film Division has stood out notably with six productions that represented 29.5% of the total box office takings for Spanish cinema in 2015. Our mission in this business area is clear: to execute, with the utmost efficiency and profitability, the obligation that the Government has imposed on us to invest in Spanish cinema, producing top quality content as a way of attracting audiences.
At Atresmedia we have been aware for years that as well as generating value for our shareholders, we also have a duty and responsibility to generate value for society and contribute positively to its progress. Compromiso Atresmedia is the result of this strong conviction and brings together all of the company's Corporate Responsibility initiatives, among which are our most famous initiatives such as Ponle Freno, HAZTE ECO, Objetivo Bienestar, Crea Cultura and Constantes y Vitales, but also the activities of Fundación Atresmedia and the Corporate Volunteering Programme in which our employees take part.
In 2015 Atresmedia joined the Red de Empresas por una Sociedad Libre de Violencia de Género (Network of Companies for a Society Free from Domestic Violence. As part of this commitment, together with the Mutua Madrileña Foundation, Antena 3 Noticias launched the Tolerancia Cero initiative to help educate about this serious problem in our society, encourage its reporting and raise awareness about it.
Ponle Freno, Constantes y Vitales and Crea Cultura have also continued recording achievements that represent significant advances for road safety, scientific research and the protection of intellectual property, respectively. Among these I would like to highlight the approval by the Congress of Deputies of the motion from Ponle Freno for the Government to make road education a mandatory subject in schools, as well as the creation of the State Research Agency demanded by Constantes y Vitales and the gold medal awarded to Crea Cultura by Federación de la Propiedad Intelectual (Intellectual Property Federation).
At Atresmedia we have been aware for years that as well as generating value for our shareholders, we also have a duty and responsibility to generate value for society and contribute positively to its progress. Compromiso Atresmedia is the result of this strong convictionHowever, 2015 also saw the tenth anniversary of Fundación Atresmedia. Ten years promoting projects that ensure the wellbeing of children, that encourage educational improvement and normalise disability, and that have benefited from the full communication potential of our media organisations and the support of our professionals.
These achievements, together with the greater accessibility of our content and platforms, the increase in the factual offering, the measures to enhance the work-life balance of our professionals and the advances made in complying with the Global Compact, reflect the strong commitment of Atresmedia to sustainability. Although we are aware that there is some way to go, we will continue promoting dialogue with our stakeholders and participating in the major multi-stakeholder corporate responsibility forums in the sector to further integrate CR into the culture of our organization and promote positive change in the society.
We are therefore looking at a year that can only be described as excellent for Atresmedia. We close 2015 with the satisfaction of having met the objectives set. Our Group continues to set the pace in the sector with attributes and values that are a benchmark for a society that appreciates what we do and who we are. 2016 will bring new challenges, new goals that will once again test us, but I am convinced that with the Group's hard work, enthusiasm and spirit of innovation and improvement, we will face these and overcome them.