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
0.17	1
0.31	2
0.45	3
0.57	4
0.67	5
0.79	6
0.88	7
0.97	8
1.05	9
1.13	10
1.20	11
1.28	12
1.35	13
1.41	14
1.48	15
1.55	16
1.62	17
1.69	18
1.76	19
1.83	20
1.89	21
1.95	22
2.01	23
2.08	24
2.14	25
2.20	26
2.27	27
2.33	28
2.40	29
2.46	30
2.52	31
2.59	32
2.65	33
2.71	34
2.77	35
2.84	36
2.91	37
2.98	38
3.03	39
3.10	40
3.16	41
3.23	42
3.29	43
3.35	44
3.42	45
3.49	46
3.55	47
3.62	48
3.70	49
3.76	50
3.83	51
3.91	52
3.99	53
4.05	54
4.14	55
4.22	56
4.28	57
4.36	58
4.44	59
4.53	60
4.60	61
4.68	62
4.77	63
4.84	64
4.94	65
5.03	66
5.12	67
5.21	68
5.31	69
5.40	70
5.51	71
5.62	72
5.73	73
5.83	74
5.93	75
6.05	76
6.19	77
6.31	78
6.45	79
6.58	80
6.72	81
6.88	82
7.07	83
7.24	84
7.45	85
7.65	86
7.84	87
8.06	88
8.25	89
8.49	90
8.79	91
9.10	92
9.50	93
9.83	94
10.32	95
10.87	96
11.65	97
12.69	98
14.38	99
25.16	100