Swimmer profile
Mac Koster
Male15-16YMCA of the Jersey ShoreNJ · EASTERN
SeasonUSA Swimming season runs Sept – Aug
Event
2019–20
2020–21
2021–22
2022–23
2023–24
2024–25
2025–26
50 Free SCY
35.88
31.83
▲ 4.05
27.81
▲ 4.02
25.66
▲ 2.15
24.08
▲ 1.58
23.58
▲ 0.50
23.98
▼ 0.40
100 Free SCY
1:19.44
—
1:00.32
▲ 19.12
56.10
▲ 4.22
52.31
▲ 3.79
52.37
▼ 0.06
53.50
▼ 1.13
200 Free SCY
2:49.24
—
2:09.59
▲ 39.65
2:05.52
▲ 4.07
1:57.25
▲ 8.27
—
2:02.34
▼ 5.09
500 Free SCY
—
—
5:45.00
5:46.97
▼ 1.97
—
—
—
1000 Free SCY
—
—
—
—
11:40.33
—
—
50 Back SCY
41.90
38.19
▲ 3.71
33.72
▲ 4.47
28.79
▲ 4.93
28.20
▲ 0.59
26.09
▲ 2.11
26.73
▼ 0.64
100 Back SCY
1:24.92
1:19.42
▲ 5.50
1:08.78
▲ 10.64
1:00.96
▲ 7.82
57.95
▲ 3.01
55.07
▲ 2.88
54.91
▲ 0.16
200 Back SCY
—
—
2:27.19
2:14.78
▲ 12.41
2:05.39
▲ 9.39
2:00.54
▲ 4.85
1:59.57
▲ 0.97
50 Breast SCY
54.31
—
—
37.29
▲ 17.02
—
—
33.09
▲ 4.20
100 Breast SCY
—
1:37.98
1:26.54
▲ 11.44
1:19.44
▲ 7.10
1:14.54
▲ 4.90
1:17.93
▼ 3.39
—
200 Breast SCY
—
—
3:08.91
2:47.43
▲ 21.48
2:40.42
▲ 7.01
—
—
50 Fly SCY
52.09
39.94
▲ 12.15
36.06
▲ 3.88
28.39
▲ 7.67
27.37
▲ 1.02
—
—
100 Fly SCY
—
—
1:23.07
1:04.66
▲ 18.41
58.84
▲ 5.82
57.09
▲ 1.75
54.51
▲ 2.58
200 Fly SCY
—
—
—
—
2:15.31
2:26.92
▼ 11.61
2:32.42
▼ 5.50
100 IM SCY
1:37.38
1:25.40
▲ 11.98
1:15.35
▲ 10.05
1:07.55
▲ 7.80
—
—
—
200 IM SCY
—
3:01.49
2:37.26
▲ 24.23
2:22.48
▲ 14.78
—
2:08.36
▲ 14.12
—
400 IM SCY
—
—
—
5:02.64
4:42.52
▲ 20.12
5:03.38
▼ 20.86
—
Improvement<0.5s0.5–2s2–5s5s+Slower
📊 All Attempts by Event
Chronological history of every recorded swim. Click an event to expand its attempt list.