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
0.03	1
0.04	2
0.04	3
0.04	4
0.05	5
0.05	6
0.06	7
0.06	8
0.07	9
0.07	10
0.08	11
0.09	12
0.09	13
0.10	14
0.11	15
0.12	16
0.12	17
0.13	18
0.14	19
0.15	20
0.16	21
0.18	22
0.19	23
0.21	24
0.22	25
0.24	26
0.26	27
0.27	28
0.29	29
0.30	30
0.31	31
0.32	32
0.34	33
0.35	34
0.36	35
0.37	36
0.39	37
0.40	38
0.41	39
0.42	40
0.43	41
0.44	42
0.46	43
0.48	44
0.48	45
0.50	46
0.51	47
0.53	48
0.53	49
0.56	50
0.57	51
0.59	52
0.60	53
0.62	54
0.63	55
0.65	56
0.67	57
0.69	58
0.71	59
0.73	60
0.75	61
0.77	62
0.79	63
0.80	64
0.83	65
0.86	66
0.88	67
0.91	68
0.92	69
0.95	70
0.97	71
1.01	72
1.03	73
1.05	74
1.07	75
1.11	76
1.14	77
1.17	78
1.20	79
1.25	80
1.28	81
1.31	82
1.36	83
1.41	84
1.45	85
1.51	86
1.56	87
1.61	88
1.68	89
1.75	90
1.84	91
1.94	92
2.05	93
2.18	94
2.35	95
2.59	96
2.92	97
3.36	98
4.40	99
18.57	100