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
0.01	1
0.02	2
0.02	3
0.03	4
0.03	5
0.04	6
0.04	7
0.05	8
0.06	9
0.06	10
0.07	11
0.08	12
0.08	13
0.09	14
0.10	15
0.11	16
0.12	17
0.13	18
0.13	19
0.14	20
0.15	21
0.16	22
0.17	23
0.18	24
0.19	25
0.20	26
0.21	27
0.22	28
0.23	29
0.24	30
0.25	31
0.26	32
0.27	33
0.28	34
0.29	35
0.31	36
0.31	37
0.33	38
0.34	39
0.35	40
0.36	41
0.38	42
0.39	43
0.40	44
0.41	45
0.43	46
0.44	47
0.46	48
0.47	49
0.48	50
0.50	51
0.52	52
0.53	53
0.55	54
0.57	55
0.59	56
0.61	57
0.63	58
0.64	59
0.66	60
0.68	61
0.71	62
0.73	63
0.75	64
0.78	65
0.80	66
0.83	67
0.86	68
0.89	69
0.92	70
0.95	71
0.99	72
1.03	73
1.06	74
1.10	75
1.14	76
1.19	77
1.24	78
1.29	79
1.34	80
1.39	81
1.44	82
1.51	83
1.58	84
1.65	85
1.73	86
1.80	87
1.89	88
1.99	89
2.10	90
2.21	91
2.33	92
2.49	93
2.70	94
2.92	95
3.21	96
3.57	97
4.15	98
4.98	99
9.68	100