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
0.11	1
0.33	2
0.44	3
0.63	4
0.74	5
0.85	6
0.93	7
1.01	8
1.08	9
1.15	10
1.24	11
1.30	12
1.35	13
1.40	14
1.45	15
1.52	16
1.59	17
1.66	18
1.71	19
1.76	20
1.81	21
1.86	22
1.91	23
1.95	24
2.00	25
2.06	26
2.11	27
2.15	28
2.20	29
2.26	30
2.31	31
2.38	32
2.42	33
2.46	34
2.52	35
2.56	36
2.60	37
2.67	38
2.71	39
2.76	40
2.81	41
2.85	42
2.91	43
2.96	44
3.02	45
3.08	46
3.12	47
3.18	48
3.22	49
3.28	50
3.32	51
3.38	52
3.43	53
3.50	54
3.56	55
3.61	56
3.68	57
3.73	58
3.79	59
3.84	60
3.91	61
3.98	62
4.05	63
4.12	64
4.17	65
4.24	66
4.31	67
4.40	68
4.48	69
4.55	70
4.62	71
4.69	72
4.75	73
4.85	74
4.95	75
5.04	76
5.11	77
5.20	78
5.32	79
5.42	80
5.53	81
5.62	82
5.79	83
5.93	84
6.04	85
6.16	86
6.32	87
6.46	88
6.63	89
6.86	90
7.08	91
7.32	92
7.60	93
7.85	94
8.30	95
8.76	96
9.32	97
9.93	98
11.57	99
19.48	100