_id	age__end_of_academic_year_	No of Pupils
1	3	5
2	4	136
3	5	557
4	6	1290
5	7	1530
6	8	1547
7	9	1393
8	10	1331
9	11	1276
10	12	1151
11	13	913
12	14	923
13	15	1062
14	16	953
15	17	811
16	18	585
17	19	339
18	20	105
19	Unkown	646
20	Total	16553