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
0.07	1
0.11	2
0.14	3
0.18	4
0.21	5
0.25	6
0.28	7
0.32	8
0.35	9
0.39	10
0.44	11
0.47	12
0.50	13
0.54	14
0.58	15
0.62	16
0.66	17
0.71	18
0.74	19
0.78	20
0.82	21
0.87	22
0.92	23
0.96	24
1.00	25
1.06	26
1.11	27
1.16	28
1.22	29
1.28	30
1.33	31
1.39	32
1.44	33
1.50	34
1.56	35
1.63	36
1.71	37
1.78	38
1.86	39
1.93	40
2.00	41
2.08	42
2.16	43
2.25	44
2.33	45
2.43	46
2.54	47
2.63	48
2.72	49
2.83	50
2.93	51
3.04	52
3.18	53
3.32	54
3.43	55
3.58	56
3.70	57
3.84	58
4.00	59
4.17	60
4.33	61
4.50	62
4.67	63
4.84	64
5.07	65
5.31	66
5.51	67
5.74	68
6.00	69
6.20	70
6.46	71
6.68	72
7.01	73
7.40	74
7.75	75
8.11	76
8.48	77
9.00	78
9.52	79
10.00	80
10.44	81
11.00	82
11.51	83
12.16	84
12.77	85
13.50	86
14.17	87
15.01	88
16.02	89
17.55	90
19.01	91
20.67	92
22.55	93
25.04	94
28.06	95
31.15	96
36.50	97
44.33	98
56.10	99
113.00	100