?????? 7? ??PCS ??? 3?27?? ???? ???? ??? ??. ‘??? ??? ????? ??? ???? ???’?? ??? 75.8%? ‘?? ??? ???? ??’? ????. ‘????? ??? ? ??? ?? ???? ? ???’? ??? 24.2%??. ‘?? ??’ ??? 20? 84.8%, 30? 79.8%, 40? ?? 49.1% ? ??? ???? ???.

????? ????? ???? ‘?? ????? ???’? ??? 63.0%? ??????. ‘?? ??? ???? ??? ????? ?? ???’? ??? 34.9%? ??. ‘????’? 2.1%.

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