The average degree, as shown in Figure 8B , presents an increasing trend over the period from P 4 to J 3 , except for a slight decrease in J 1 , and a descending trend in the senior high school years.
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The average degree, as shown in Figure 8B , presents an increasing trend over the period from P 4 to J 3 , except for a slight decrease in J 1 , and a descending trend in the senior high school years.