Safety Measurement System

Measure vs. Percentile

Carrier violations or crashes are weighted by time and severity to produce a measure for that carrier in each BASIC. The measure is then used to assign that carrier to a percentile rank containing carriers’ information in similar safety event groups. Expand for more information.

Carrier violations or crashes are weighted by time and severity to produce a measure for that carrier in each BASIC. The measure only considers individual performance based on 24 months of data, with a measure of 0 indicating best performance. The measure is then used to assign that carrier to a percentile rank containing carriers’ information in similar safety event groups. The graph below shows how the carrier’s measure correlates with its percentile rank over a selected period of time.

Measure

Percentile

Measure	Percentile
0	0
0.08	1
0.12	2
0.16	3
0.21	4
0.25	5
0.29	6
0.33	7
0.36	8
0.39	9
0.43	10
0.47	11
0.50	12
0.54	13
0.59	14
0.63	15
0.67	16
0.71	17
0.75	18
0.79	19
0.83	20
0.87	21
0.92	22
0.97	23
1.01	24
1.06	25
1.11	26
1.17	27
1.23	28
1.29	29
1.34	30
1.39	31
1.45	32
1.49	33
1.53	34
1.60	35
1.67	36
1.73	37
1.79	38
1.87	39
1.95	40
2.00	41
2.10	42
2.18	43
2.27	44
2.35	45
2.43	46
2.53	47
2.65	48
2.73	49
2.83	50
2.94	51
3.01	52
3.15	53
3.24	54
3.36	55
3.50	56
3.62	57
3.75	58
3.88	59
4.00	60
4.20	61
4.34	62
4.50	63
4.68	64
4.83	65
5.00	66
5.21	67
5.44	68
5.67	69
5.87	70
6.17	71
6.36	72
6.64	73
7.01	74
7.33	75
7.61	76
7.98	77
8.29	78
8.64	79
9.02	80
9.50	81
10.02	82
10.50	83
11.13	84
11.71	85
12.40	86
13.02	87
13.86	88
14.99	89
15.77	90
17.02	91
18.54	92
20.33	93
22.54	94
25.04	95
28.99	96
34.28	97
41.15	98
53.22	99
108.00	100