Time Interval

Failures

n remaining

Failure rate from actual count

Conditional probability of failure

Failure rate out of max. possible

Maximum number of THAs remaining

6 months

57

8299

0.7%

-

0.6%

9943

1 year

9

7921

0.1%

0.9%

0.1%

9943

3 years

58

7129

0.8%

0.5%

0.7%

8847

5 years

64

5900

1.1%

0.7%

0.8%

8068

7 years

82

4753

1.7%

0.8%

1.1%

7305

10 years

129

3650

3.5%

1.6%

2.1%

6166

12 years

94

2348

^*

2.5%

1.7%

5439

15 years

78

1652

^*

^*

1.7%

4537

17 years

42

948

^*

^*

1.1%

3903

20 years

41

604

^*

^*

1.4%

3016

22 years

17

299

^*

^*

0.8%

2035

25 years

17

175

^*

^*

0.9%

1823

25⁺ years

6

94

^*

^*

0.4%

1652