Table 1.
20-m SRT (number of laps) centiles by age and sex for 69,960 Chinese children and youth aged 9–17 years.
Age(yr)
P
5
P
10
P
20
P
30
P
40
P
50
P
60
P
70
P
80
P
90
P
95
Boy
9
8
10
13
15
18
20
23
26
29
35
40
10
9
12
15
18
21
23
26
30
34
41
47
11
11
14
18
21
24
27
30
34
39
47
53
12
13
16
20
24
28
31
35
39
45
53
61
13
14
18
23
27
31
35
40
45
51
60
69
14
16
20
26
30
35
39
44
49
56
67
76
15
17
22
28
33
37
42
47
53
60
72
82
16
19
23
29
35
40
44
50
56
64
75
86
17
19
24
31
36
41
46
52
58
66
78
89
Girls
9
8
10
13
15
17
19
21
24
27
32
37
10
10
12
14
17
19
21
24
27
31
36
42
11
11
13
16
19
21
24
26
30
34
40
46
12
12
14
17
20
23
26
29
32
36
43
50
13
12
15
19
22
24
27
30
34
39
46
52
14
13
16
20
23
26
29
32
35
40
48
55
15
14
16
20
23
26
29
33
37
41
49
56
16
14
17
21
24
27
30
33
37
42
50
57
17
14
17
21
24
27
31
34
38
43
50
58
Ages shown represent age at last birthday (e.g. 9 = 9.0–9.99).