21.   Instead, Internet use itself appeared to cause a decline in psychological well-being, the researchers said.

22.   Is overfishing causing a decline in the fish that sharks prey upon, causing them to seek other food sources?

23.   Jack Loftus, a spokesman for Nielsen, said it has done nothing different in selecting its sample of households for the national rating that would cause the declines.

24.   Kurt M. Ribisl a professor of public health at the University of North Carolina, said that no state tax increase had ever caused a decline in revenue.

25.   Local newspapers have been reporting that the stepped-up police presence in San Diego has caused a decline in crime.

26.   Like police officials, Skolnick said the prosperous economy has caused the decline.

27.   Moreover, no one knows exactly what caused the decline.

28.   Murphy said much of the burned land has been fire-starved too long, causing a decline of native, fire-adapted plants and wildlife.

29.   Nissan said a deliberate reduction in its sales to fleet buyers caused the decline.

30.   Of course, it is not just the restrictions on English on commercial signs that has caused the decline.