Out of 503 films released in the UK in 2009, 31 of them accounted for suspense films. Even though they accounted for 4% of box office takings and action, animation and comedy for more than half, the reason is because suspense films appeal to a specific audience whereas the other appealed to the masses.
According to the 'genre by gender' diagram, women tend to go for romantic, period and suspenseful films whereas men go for crime, action and sci-fi films. Horror, however, is somewhere in between the two appealing to both men and women. Thrillers tend to be crime, action and horror based therefore they attract a more masculine audience.