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
0.02	1
0.02	2
0.03	3
0.03	4
0.04	5
0.05	6
0.05	7
0.06	8
0.07	9
0.07	10
0.08	11
0.09	12
0.10	13
0.11	14
0.12	15
0.13	16
0.13	17
0.14	18
0.15	19
0.16	20
0.17	21
0.18	22
0.19	23
0.20	24
0.21	25
0.22	26
0.23	27
0.24	28
0.25	29
0.26	30
0.28	31
0.29	32
0.30	33
0.31	34
0.32	35
0.34	36
0.35	37
0.36	38
0.37	39
0.39	40
0.40	41
0.41	42
0.43	43
0.44	44
0.46	45
0.47	46
0.49	47
0.50	48
0.52	49
0.53	50
0.55	51
0.57	52
0.58	53
0.60	54
0.62	55
0.64	56
0.66	57
0.68	58
0.70	59
0.72	60
0.74	61
0.77	62
0.79	63
0.82	64
0.84	65
0.87	66
0.90	67
0.93	68
0.96	69
1.00	70
1.02	71
1.05	72
1.09	73
1.13	74
1.16	75
1.20	76
1.24	77
1.28	78
1.33	79
1.38	80
1.44	81
1.50	82
1.55	83
1.61	84
1.67	85
1.75	86
1.82	87
1.90	88
2.00	89
2.10	90
2.21	91
2.33	92
2.47	93
2.64	94
2.83	95
3.09	96
3.39	97
3.81	98
4.45	99
8.96	100