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
0.10	1
0.25	2
0.39	3
0.56	4
0.68	5
0.78	6
0.85	7
0.94	8
0.98	9
1.06	10
1.11	11
1.15	12
1.23	13
1.28	14
1.34	15
1.38	16
1.42	17
1.46	18
1.50	19
1.55	20
1.60	21
1.65	22
1.69	23
1.75	24
1.80	25
1.83	26
1.88	27
1.93	28
1.98	29
2.04	30
2.07	31
2.12	32
2.17	33
2.21	34
2.24	35
2.30	36
2.35	37
2.40	38
2.44	39
2.47	40
2.51	41
2.56	42
2.61	43
2.65	44
2.70	45
2.75	46
2.80	47
2.84	48
2.89	49
2.94	50
2.99	51
3.05	52
3.11	53
3.15	54
3.18	55
3.22	56
3.27	57
3.32	58
3.37	59
3.43	60
3.49	61
3.56	62
3.62	63
3.68	64
3.73	65
3.79	66
3.84	67
3.89	68
3.96	69
4.03	70
4.09	71
4.16	72
4.22	73
4.31	74
4.38	75
4.45	76
4.51	77
4.60	78
4.67	79
4.75	80
4.82	81
4.94	82
5.03	83
5.13	84
5.25	85
5.39	86
5.52	87
5.71	88
5.92	89
6.09	90
6.34	91
6.62	92
6.88	93
7.15	94
7.47	95
7.82	96
8.29	97
9.15	98
10.97	99
20.89	100