The efforts of Al Gore and other environmental campaigns have focused on the effects of global warming and have managed to increase awareness and concern, but despite these efforts, the number of Americans believing humans are the cause of global warming was holding steady at 61% in 2007, and those believing the popular media was understating the issue remained about 35%. A recent poll from 2015 suggests that while Americans are growing more aware of the dangers and implications of climate change for future generations, the majority are not worried about it. From a survey conducted in 2004, it was found that more than 30% of news presented in the previous decade showed equal attention to both human and non human contributions to global warming.