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
0.08	10
0.08	11
0.09	12
0.09	13
0.10	14
0.11	15
0.12	16
0.13	17
0.13	18
0.14	19
0.15	20
0.17	21
0.18	22
0.19	23
0.21	24
0.23	25
0.25	26
0.26	27
0.28	28
0.29	29
0.31	30
0.32	31
0.34	32
0.35	33
0.36	34
0.37	35
0.38	36
0.39	37
0.40	38
0.42	39
0.43	40
0.44	41
0.46	42
0.47	43
0.48	44
0.50	45
0.51	46
0.53	47
0.54	48
0.56	49
0.57	50
0.59	51
0.61	52
0.63	53
0.64	54
0.67	55
0.68	56
0.69	57
0.71	58
0.73	59
0.75	60
0.77	61
0.80	62
0.82	63
0.84	64
0.86	65
0.88	66
0.91	67
0.92	68
0.95	69
0.97	70
1.01	71
1.02	72
1.05	73
1.07	74
1.11	75
1.14	76
1.16	77
1.20	78
1.22	79
1.25	80
1.30	81
1.34	82
1.37	83
1.43	84
1.48	85
1.54	86
1.58	87
1.66	88
1.72	89
1.80	90
1.89	91
2.01	92
2.11	93
2.26	94
2.42	95
2.63	96
2.87	97
3.34	98
4.08	99
11.13	100