A New Zealand-based psychologist, James Flynn, observed that average IQ rises 3 percent every decade. However, this started to slow down from the mid-1990s, and by the early 2000s, IQ scores started dropping. Caroline Williams speculates in [[Move!]] that this is due to our increasingly sedentary lifestyles. A study showed that physical activity declined the fastest in the 1990s in countries such as China and Brazil.