Sentence:  In contrast , 20 of the 21 lines in the Completion Profile ( excluding center 5 for boys and 4 for girls ) are bunched and extend over a much <WSD>shorter</WSD> period , approximately 30 months for boys and 40 months for girls . 
Meaning of the word marked with <WSD> tags:  primarily temporal sense; indicating or being or seeming to be limited in duration