In the following items, each passage consists of six sentences. The first sentence (S1) and the final sentence (S6) are given. The middle four sentences in each have been removed and jumbled up. These are labelled P, Q, R and S. You are required to find out the proper sequence of the four sentences and mark accordingly on the Answer Sheet. 

S1: People have always been fascinated by dreams. 
P: In fact, only recently have there been serious studies to find out how many of us actually have nightmares. 
Q: Now that is changing. 
R: But the study of nightmares has been curiously neglected.
S: While results so far are inconclusive, it seems fair to say that at least half the population has occasional nightmares. 
S6: But a small number, perhaps less than 5% have them regularly.