NEW YORK (TheStreet) -- Content may be king, but sometimes there's just too much of it.
Among the many problems confronting the largest U.S. television networks, one appears to be of its own making: Big Media is producing more original programming than anyone has time to watch. The trend of producing more programming comes as viewers, especially younger viewers, are spending more of their time at user-generated venues such as Google's (GOOG) YouTube and IAC Interactive's (IACI) Vimeo, and subscription video services, especially Netflix (NFLX) but also Amazon (AMZN) Prime, all accessible through devices such as Roku and Apple's (AAPL) AppleTV.
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TV content is growing at a rate of 12% a year, while the time that the average U.S. viewer watches television is increasing by just 2%, according to a Barclays research report on U.S. media by Kannan Venkateshwar. Time Warner (TWX) , to cite just one example, is doubling its spending on original programming at TNT and TBS over the next four years from $500 million to $1 billion.
The result is a decline in TV ratings amid increasing signs advertisers are skimming more of their TV money into digital.
"This crowding is likely to result in cannibalization across the platform that gets the most viewership today, i.e., TV," wrote Venkateshwar. "Consequently, if digital advertising continues to grow at the same pace that has been seen over the last decade, then the segment that could suffer next could be TV."
When Disney (DIS) , CBS (CBS) , Time Warner and 21st Century Fox (FOXA) report third-quarter earnings this week, and answer Wall Street analyst questions about advertising trends for the current quarter, we'll get a better sense of how quickly advertising dollars are moving away from television.
Early indications point toward a decline. According to data compiled by Standard Media Index, an industry monitor, third-quarter television advertising fell 4% for the three-month period ended Sept. 30. Considering that the decline in the second quarter was 1%, the television industry may be at an historic crossroads as forecasters such as Forrester Research project U.S. spending on Internet display ads to almost double over the next five years to $37.6 billion by 2019 compared to $19.8 billion in 2014.