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
0.23	1
0.36	2
0.51	3
0.63	4
0.75	5
0.86	6
0.97	7
1.08	8
1.17	9
1.27	10
1.35	11
1.45	12
1.55	13
1.64	14
1.74	15
1.83	16
1.91	17
2.01	18
2.10	19
2.19	20
2.27	21
2.36	22
2.45	23
2.53	24
2.62	25
2.70	26
2.79	27
2.88	28
2.96	29
3.05	30
3.15	31
3.24	32
3.32	33
3.41	34
3.50	35
3.59	36
3.68	37
3.76	38
3.87	39
3.95	40
4.04	41
4.12	42
4.21	43
4.30	44
4.40	45
4.51	46
4.59	47
4.69	48
4.79	49
4.88	50
4.97	51
5.07	52
5.16	53
5.28	54
5.39	55
5.49	56
5.59	57
5.71	58
5.83	59
5.96	60
6.07	61
6.18	62
6.29	63
6.41	64
6.54	65
6.67	66
6.81	67
6.96	68
7.09	69
7.22	70
7.35	71
7.51	72
7.62	73
7.76	74
7.91	75
8.06	76
8.22	77
8.41	78
8.59	79
8.78	80
9.00	81
9.17	82
9.39	83
9.64	84
9.87	85
10.10	86
10.35	87
10.62	88
10.90	89
11.29	90
11.66	91
12.05	92
12.56	93
13.06	94
13.69	95
14.44	96
15.31	97
16.44	98
18.50	99
28.69	100