Actuarial Experience Studies:
Mortality
By
Mortality Experience Studies - Content
• Use of Mortality Experience
• Source of Mortality Studies
• Best Estimate Assumptions
• Margin for Adverse Deviation
• Experience Studies
• Exposure Measurement • Credibility
Use of Mortality Experience
•
Valuation
•
Pricing
•
Products without mortality Risk?
• Still needed as mortality could be a contingency with respect to persistency
•
Life insurance
•
Life annuity
Source of Mortality Studies
•
Industry Studies / Mortality Tables
• Representative of your Company’s experience?
• Indonesia vs Other Countries (e.g. US Society of Actuaries (SOA) mortality tables)
• May not be representative due to differences in underwriting standards, socio economic factors, etc
•
Population Mortality
• Not representative of insured mortality (re: underwriting)
•
Reinsurers’ experience
•
Own experience
• Most Relevant
• Credibility
•
Important to understand the experience underlying the mortality table
• Insured mortality
• Basis of the table (e.g. SOA tables are valuation tables and include “built in” margins)
• Period of observation – experience may be dated and mortality improvements / deterioration may be required to make the table current
Best Estimate Assumption – Data Differentiation
•
Life insured’s/Annuitant’s age, sex, smoking habit, health, lifestyle
•
Duration since issue of policy
•
Plan of insurance (e.g. term, whole life) and its benefit provided
•
Company’s underwriting practice
•
Size of policy
•
Company’s distribution system (e.g. agency, brokerage, etc.) and marketing
practice
•
Each “cell” should be as homogeneous as possible
Margin for Adverse Deviation(MfAD)
• MfAD should increase the liability – requires testing of “direction” of MfAD (i.e. increasing or reducing the best estimate assumption)
• Size of MfAD reflects the degree of uncertainty of the best estimate assumption
• Uncertainty relates to misestimation of and deterioration from the best estimate assumption
• Canadian Standard for life insurance: K / ex per 1,000 lives
• High Margin: K = 15
• Low Margin: K = 3.75 (i.e. 25% of High Margin) • Canadian Standard for annuities
• High Margin: -20%
• Low Margin: -5%
• Selection of High or Low margin depends on “Significant Considerations”
Margin for Adverse Deviation(MfAD) - continued
• Significant Considerations – Misestimation of best estimate assumption:
• Low credibility of the Company’s own experience
• Lack of homogeneity
• Unrefined method used to determine best estimate assumption (e.g. using single equivalent age for joint policies instead of each individual age)
• Change in underwriting practice in the Company
• Significant Consideration – Deterioration of best estimate assumption:
• Anti-selection is present (e.g. re-entry products; underwriting, sales force)
• Unfavourable mortality developments have emerged (e.g. AIDS)
• Persistency rate of product is low
• Premium structure does not recognize mortality differentials as precisely as the rest of the market (e.g. unisex rates; no distinction between smokers/non-smokers)
• Similar considerations apply to annuity business
• But favourable mortality developments would be important consideration
Experience Studies – Best Estimate Assumption
•
q
x= Deaths / Exposure
•
Exposure to risk
• Critical Element of experience studies
•
Deaths refer to Actual Claims
• Reconcile to Claims registry/P&L
• Use annuity payments for annuitant mortality experience
•
Compute based on count (i.e. number of deaths) and amount
Exposure - Measurement
• Study Period
• Include all policies exposed to risk during the period
• Need to determine entry point and exit point
• Entry Point:
• Start of exposure period for policies in-force at the beginning of the study period
• Issue date of policy for new business • Exit Point:
• End of exposure period for policies in-force at the end of the study period
• Date of termination for other policies
• Cause of Termination is an important consideration
• Death claims exposed to the end of the year of death
• Lapses/surrenders – exposed to the date of termination
• This would be reversed if doing lapse study: lapsed policies exposed for the full period but terminations due to death/surrender exposed only date of termination
• Treatment of late reported claims?
• Included in the year of study
• Best to perform study a few months after close of observation period to reduce the number of late reported claims
Exposure – Measurement
Beginning
A lives, age x
Ending
B lives, aged x+1
D deaths during the period
New Entrants
n lives, aged x+r
Withdrawals
w lives, aged x+s
0
r
s
1
Exposure – Measurement
Beginning
A lives, age x
Ending
B lives, aged x+1
D deaths during the period
New Entrants
n lives, aged x+r
Withdrawals
w lives, aged x+s
0
r
s
1
D = A * q
x+ n *
1-rq
x+r– w *
1-sq
x+sExposure – Mortality for periods less than 1 year
• Balducci formula:
1-t qx+t= (1-t) * q x, 0 ≤ t ≤ 1 • Simple assumption to compute exposure
• Alternate Formulas:
• Uniform distribution of deaths
• tqx = t * q x, 0 ≤ t ≤ 1
• 1-t qx+t= (1-t) * q x, / (1-t*qx) 0 ≤ t ≤ 1
• Constant force of mortality
• tq x= 1- (1-qx) t, 0 ≤ t ≤ 1
• 1-tq x+t = 1- (1-qx) (1-t) , 0 ≤ t ≤ 1
Exposure – Measurement
Beginning
A lives, age x
Ending
B lives, aged x+1
D deaths during the period
New Entrants
n lives, aged x+r
Withdrawals
w lives, aged x+s
0
r
s
1
D = A * q
x+ n *
1-rq
x+r– w *
1-sq
x+sUsing Balducci,
D = A * q
x+ n * (1-r) * q
x– w * (1-s) q
xD = q
x* [ A + n * (1-r) – w * (1-s) ]
With q
x= D / E, we have
Exposure – Measurement – Example 1
Beginning
A lives, age x
Ending
B lives, aged x+1
D deaths during the period
New Entrants
n lives, aged x+r
Withdrawals
w lives, aged x+s
0
r
s
1
In the above observation period, we have:
A = 1,000
Exposure – Measurement – Example 1 - Solution
Beginning
A lives, age x
Ending
B lives, aged x+1
D deaths during the period
New Entrants
n lives, aged x+r
Withdrawals
w lives, aged x+s
0
r
s
1
Solution:
First Step: Determine Number of Deaths D
B = A + n – w – D
D = A + n – w - B
D = 1,000 + 40 – 30 - 990
D = 20
Exposure – Measurement – Example 1 - Solution
Beginning
A lives, age x
Ending
B lives, aged x+1
D deaths during the period
New Entrants
n lives, aged x+r
Withdrawals
w lives, aged x+s
0
r
s
1
Solution:
Second Step: Determine Exposure assuming Balducci
E = A + (1-r) * n – (1-s) * w
Exposure – Measurement – Example 1 - Solution
Beginning
A lives, age x
Ending
B lives, aged x+1
D deaths during the period
New Entrants
n lives, aged x+r
Withdrawals
w lives, aged x+s
0
r
s
1
Solution:
Third Step: Calculate q
xq
x= D / E
q
x= 20 / 1,020
q
x≈
0.0196
Example
• Calculate Exposure contributed for each of the following lives.
• Observation period begins March 1, 2000.
• Balducci hypothesis is assumed.
Case
Birth Date
Other Facts
1
Oct. 1, 1980
Withdrew Feb. 1, 2002
2
Dec. 1, 1981
Died Apr. 1, 2003
3
Apr. 1, 1979
Died May 1, 2004
4
Mar. 1, 1980
Died Apr. 1, 2000
Example 2 - Solution
Case
Birth Date
Other Facts
1
Oct. 1, 1980
Withdrew Feb. 1, 2002
19 Exposure Period - Calendar Year
Year
Number of
Months Description
2000 10 Mar 1 - Dec 31 2001 12 Jan 1 - Dec 31 2002 1 Jan 1 - Jan 31
Total 23
Age at Entry 19 5/12
Exposure Period - By Age
Age
Number of
Months Description
19 7 Mar 1, 2000 - Sept 30, 2000 20 12 Oct 1, 2000 - Sept 30, 2001 21 4 Oct 1, 2001 - Jan 31, 2002
Total 23
Oct 1, 1999
Entry Mar 1, 2000
Exit Feb 1, 2002
Example 2 - Solution
Case
Birth Date
Other Facts
2
Dec 1, 1981
Died April 1, 2003
Exposure Period - Calendar Years Year
Number of
Months Description
2000 10 Mar 1 - Dec 31
2001 12 Jan 1 - Dec 31
2002 12 Jan 1 - Dec 31
2003 11 Jan 1 - Nov 30
Total 45 Age at Entry 18 3/12
Exposure Period - By Age Age
Number of
Months Description
18 9 Mar 1, 2000 - Nov 30, 2000 19 12 Dec 1, 2000 - Nov 30, 2001 20 12 Dec 1, 2001 - Nov 30, 2002 21 12 Dec 1, 2002 - Nov 30, 2003
Total 45
Dec 1, 1999
Entry Mar 1, 2000
Died Apr 1, 2003
Dec 1, 2000 Dec 1, 2001 Dec 1, 2002 Dec 1, 2003
Example 2 - Solution
Case
Birth Date
Other Facts
3
Apr 1, 1979
Died May 1, 2004
21 Note: Since the termination is by death, we give a full year of exposure in the year of death
Exposure Period - Calendar Years
Year
Number of
Months Description 2000 10 Mar 1 - Dec 31 2001 12 Jan 1 - Dec 31 2002 12 Jan 1 - Dec 31 2003 12 Jan 1 - Dec 31 2004 12 Jan 1 - Dec 31 2005 3 Jan 1 - Mar 31
Total 61
Age at Entry 20 11/12
Exposure Period - By Age
Age
Number of
Months Description
20 1 Mar 1, 2000 - Mar 31, 2000 21 12 Apr 1, 2000 - Mar 31, 2001 22 12 Apr 1, 2001 - Mar 31, 2002 23 12 Apr 1, 2002 - Mar 31, 2003 24 12 Apr 1, 2003 - Mar 31, 2004 25 12 Apr 1, 2004 - Mar 31, 2005
Total 61
Apr 1, 1999 Entry Mar 1, 2000
Died May 1, 2004
Apr 1, 2000 Apr 1, 2001 Apr 1, 2002 Apr 1, 2003
Exit Apr 1, 2005
Example 2 - Solution
Case
Birth Date
Other Facts
4
Mar 1, 1980
Died Apr 1, 2000
Exposure Period - Calendar Years
Year
Number of
Months Description
2000 10 Mar 1 - Dec 31 2001 2 Jan 1 - Feb 28
Total 12
Age at Entry 20
Exposure Period - By Age
Age
Number of
Months Description
20 12 Mar 1, 2000 - Feb 28, 2001
Total 12
Mar 1, 2000
Entry Mar 1, 2000
Died Apr 1, 2000
Mar 1, 2001
Example 2 - Solution
Case
Birth Date
Other Facts
5
Nov 1, 1980
Withdrew Aug. 1, 2004
23
Exposure Period - Calendar Years
Year
Number of
Months Description
2000 10 Mar 1 - Dec 31
2001 12 Jan 1 - Dec 31
2002 12 Jan 1 - Dec 31
2003 12 Jan 1 - Dec 31
2004 7 Jan 1 - Jul 31
Total 53
Age at Entry 19 4/12
Exposure Period - By Age
Age
Number of
Months Description
19 8 Mar 1, 2000 - Oct 31, 2000 20 12 Nov 1, 2000 - Oct 31, 2001 21 12 Nov 1, 2001 - Oct 31, 2002 22 12 Nov 1, 2002 - Oct 31, 2003 23 9 Nov 1, 2003 - Jul 31, 2004
Total 53
Nov 1, 1999
Entry Mar 1, 2000
Nov 1, 2000 Nov 1, 2001 Nov 1, 2002 Nov 1, 2003
Exit Aug 1, 2004
Credibility
•
Function of number of claims
• CIA Educational Note sets 100% credibility at 3,007 death claims (based on Poisson distribution; 90% confidence interval with 3% margin of error)
•
Use to blend own experience with industry experience
• Assumption that Industry Tables are 100% credible
•
Blended q
x= Z * own experience + (1-Z) * Industry experience
•
Z is credibility factor = minimum { (Number of Claims / 3007) ^ (1/2) , 1 }
•
Examples of Credibility Factors
Number
of
Claims
Example 3
• Calculate Actual-to-Expected experience by number of lives and by amounts based on the following data
• Calculate Credibility at age 22, assuming 3,007 claims for full credibility
• If e52= 28.89, calculate the Margin for Adverse Deviation (MfAD) for High Margin situations and total “valuation” mortality at age 52 based on Canadian Actuarial Standards of Practice
Exposure
Actual Claims
Age
1000 q
xNumber
Amount
Number
Amount
22
.67
471,797
17,119,826
196
6,685
37
.90
660,127
29,317,759
661
23,777
52
2.91
1,549,048
93,872,023
4,506
228,785
67
16.32
1,098,383
36,781,306
12,720
335,609
82
64.87
534,162
8,686,284
28,878
430,786
Example 3 - Solution
• Step 1 – Calculate Expected Claims
• Expected Claims = Exposure * qx
Age
1000 q
xNumber
Amount
Number
Amount
22
0.67
471,797
17,119,826
316
11,470
37
0.90
660,127
29,317,759
594
26,386
52
2.91
1,549,048
93,872,023
4,508
273,168
67
16.32
1,098,383
36,781,306
17,926
600,271
82
64.87
534,162
8,686,284
34,651
563,479
Example 3 - Solution
• Step 2 – Actual to Expected
• A / E = Actual Claims divided by Expected Claims
27
Age
Number
Amount
Number
Amount
Number
Amount
22
196
6,685
316
11,470
62%
58%
37
661
23,777
594
26,386
111%
90%
52
4,506
228,785
4,508
273,168
100%
84%
67
12,720
335,609
17,926
600,271
71%
56%
82
28,878
430,786
34,651
563,479
83%
76%
TOTAL
46,961
1,025,642
57,995
1,474,774
81%
70%
Example 3 – Solution
•
Calculate Credibility at age 22, assuming 3,007 claims for full
credibility
•
Solution:
•
Credibility = minimum { (Actual Claims / 3007) ^ 0.5, 100%}
•
Actual Claims [22] = 196
•
Credibility = minimum { (196 / 3007) ^ 0.5 , 100%}
Example 3 - Solution
•
If e
52= 28.89, calculate the Margin for Adverse Deviation (MfAD) for
High Margin situations and total “valuation” mortality at age 52
based on Canadian Actuarial Standards of Practice
•
Solution:
•
MfAD [x] = K / e
x ,per 1,000, with k = 15 for High Margin situations
•
MfAD [52] = 15 / 28.89 per 1,000
•
MfAD [52] = 0.52 per 1,000
•
Total Valuation Assumption = Best Estimate Assumption + MfAD (*)
•
Total q
52= 2.91 per 1,000 + 0.52 per 1,000
•
Total q
52= 3.43 per 1,000
29
Best Estimate Assumption – Additional Considerations
•
Persistency
• Anti-selective lapses
•
Underwriting Practices
• Medical
• Non-medical
•
Mortality Improvement
• Project current mortality from dated studies
• Required for annuity business
• Accepted practice in Canada
• Typical approach:
• qx,n = qx * (1 – improvement) n, where n is number of years since the study of the
underlying qxwas performed
•
“Back-to-Back” contracts
Example 4
• You are given the following qx for males based on a mortality study centered in 2010
• Assuming 2% annual mortality improvement, calculate the qx for a policy issued in 2012 for a male aged 25 at issue
Age
1000 q
xAdjusted 1000 q
x25
.76
26
.78
27
.80
28
.81
29
.82
Example 4 - Solution
• Step 1 – Determine number of elapsed years since the mortality study
Age
Attained Year
Elapsed Years
25
2012
2
26
2013
3
27
2014
4
28
2015
5
Example 4 - Solution
• Step 2 – Determine mortality improvement factor by elapsed year since study
Age
Elapsed
Years
Improvement
25
2
Improvement factor [2] = (1-2%) ^ 2 = 0.9604
26
3
Improvement factor [3] = (1-2%) ^ 3 = 0.9412
27
4
Improvement factor [4] = (1-2%) ^ 4 = 0.9224
28
5
Improvement factor [5] = (1-2%) ^ 5 = 0.9039
29
6
Improvement factor [6] = (1-2%) ^ 6 = 0.8858
Example - Solution
• Step 3 – Calculate the adjusted q x
• Adjusted qx,n= base qx * improvement factor [n], where n is the elapsed number of years since the mortality study.
Age
Base
1000 q
xImprovement
Factor
Adjusted 1000 q
x25
.76
0.9604
.730
26
.78
0.9412
.734
27
.80
0.9224
.738
28
.81
0.9039
.732
Sources of Information
• Canadian Institute of Actuaries Standards of Practice
• Canadian Institute of Actuaries Educational Notes:
• Expected Mortality: Fully Underwritten Canadian Individual Life Insurance Policies
• Margins for Adverse Deviation
• Society of Actuaries Mortality Table Construction (Batten) , Prentice Hall, 1978