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
0.18	1
0.34	2
0.47	3
0.59	4
0.69	5
0.80	6
0.90	7
0.98	8
1.06	9
1.14	10
1.23	11
1.32	12
1.40	13
1.46	14
1.53	15
1.60	16
1.67	17
1.74	18
1.81	19
1.88	20
1.94	21
2.01	22
2.08	23
2.14	24
2.20	25
2.27	26
2.34	27
2.41	28
2.47	29
2.54	30
2.60	31
2.67	32
2.74	33
2.81	34
2.90	35
2.96	36
3.02	37
3.09	38
3.15	39
3.22	40
3.29	41
3.36	42
3.43	43
3.50	44
3.56	45
3.63	46
3.71	47
3.79	48
3.86	49
3.93	50
4.01	51
4.09	52
4.16	53
4.24	54
4.33	55
4.40	56
4.49	57
4.56	58
4.65	59
4.73	60
4.81	61
4.90	62
4.99	63
5.09	64
5.18	65
5.28	66
5.37	67
5.47	68
5.58	69
5.69	70
5.80	71
5.89	72
6.00	73
6.12	74
6.24	75
6.37	76
6.51	77
6.66	78
6.79	79
6.93	80
7.08	81
7.25	82
7.42	83
7.60	84
7.80	85
7.98	86
8.20	87
8.41	88
8.67	89
8.93	90
9.20	91
9.59	92
9.94	93
10.38	94
10.86	95
11.47	96
12.25	97
13.47	98
15.26	99
25.54	100