Difference between revisions of "Friedland08.ExpectedClms"
(→Example A: Very Easy) |
(→Example B: Estimating ECR using Loss Trends) |
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: '''annual loss trend''' = 2% | : '''annual loss trend''' = 2% | ||
− | Then we can insert | + | Then we can insert 2 columns into the table above for the trend factor and '''trended''' ultimate losses. |
+ | |||
+ | :{| class='wikitable' style='text-align: center;' | ||
+ | |- | ||
+ | ! AY !! OLEP !! ultimate <br> losses !! trend <br> factor !! trended <br> ultimate <br> losses !! ultimate <br> losses <br> ratio | ||
+ | |- | ||
+ | || '''2017''' || 1,000 || 750 || 1.02<sup>4 || || 75% | ||
+ | |- | ||
+ | || '''2018''' || 1,000 || 750 || 1.02<sup>3 || 75% | ||
+ | |- | ||
+ | || '''2019''' || 1,000 || 750 || 1.02<sup>2 || 75% | ||
+ | |- | ||
+ | || '''2020''' || 1,000 || 750 || 1.02<sup>1 || 75% | ||
+ | |- style='border-top: 2px solid; background-color: gainsboro;' | ||
+ | || '''2021''' || 1,000 || ? || '''ECR = 75%''' | ||
+ | |} | ||
==POP QUIZ ANSWERS== | ==POP QUIZ ANSWERS== |
Revision as of 17:56, 30 June 2020
Reading: Friedland, J.F., Estimating Unpaid Claims Using Basic Techniques, Casualty Actuarial Society, Third Version, July 2010. The Appendices are excluded.
Chapter 8: Expected Claims Method
Contents
Pop Quiz
Study Tips
BattleTable
Based on past exams, the main things you need to know (in rough order of importance) are:
- fact A...
- fact B...
reference part (a) part (b) part (c) part (d) E (2017.Spring #18) unpaid & IBNR:
- ECR methodFriedland09.BornFerg E (2016.Spring #16) unpaid claims:
- ECR methodFriedland07.Development Friedland09.BornFerg E (2015.Fall #17) Friedland07.Development ultimate claims:
- ECR method with trendE (2015.Spring #18) ultimate claims:
- ECR method with trendE (2014.Fall #15) IBNR:
- ECR method with trendE (2014.Spring #19) ultimate claims:
- ECR method with trend
In Plain English!
Example A: Intro to ECR Method
Recall that LR normally stands for Loss Ratio, and that this is the same things as CR or Claims Ratio. Let ECR stand for Expected Claims Ratio (this is an ultimate value) ECR is a projection, or an expectation of what the loss ratio or claims ratio is going to be in a future period. Let's start with a very simple example of the ECR method. Suppose you're given:
- ECR = 75% (based on historical CRs from the past few years which were all 75%)
- EP = 1,000
Then by the ECR method:
- ultimate claims = ECR x EP = 75% x 1,000 = 750
To say this in words, if you think the ultimate claims ratio for a particular year is going to be 75%, and you also know the EP is 1,000, then the ultimate claims (in dollars) is obviously just the product of ECR and EP. Let's extend this example a little bit by supposing you also know:
- paid loss = 600
- reported loss = 850
Then using Alice's Pro Tip & Mega-Useful Formulas we can calculate the following:
- IBNR = (ultimate loss) – (reported loss) = 1,000 – 850 = 150
- case O/S = (reported loss) – (paid loss) = 850 – 600 = 250
Then it's an easy matter to get:
- total unpaid = (case O/S) + (IBNR) = 250 + 150 = 400
This is all you need to know to do part (a) of these 2 exam problems. Give them a try now. They should only take a few minutes each.
The above 2 exam problems are also included in the quiz so you can keep track of how you did on them and also when you last did them.
mini BattleQuiz 1 You must be logged in or this will not work.
Example B: Estimating ECR using Loss Trends
In the previous example the actuary came up with an estimate of 75% for the ECR just by looking at past years and assumed nothing would change going forward. The data may have looked something like this:
AY OLEP ultimate
claimsultimate
claims
ratio2017 1,000 750 75% 2018 1,000 750 75% 2019 1,000 750 75% 2020 1,000 750 75% 2021 1,000 ? ECR = 75%
Projecting an ECR of 75% for AY 2021 looks reasonable, but estimating the ECR is the key to this method so let's see if we can be a little more sophisticated. Suppose you're also given the following:
- annual loss trend = 2%
Then we can insert 2 columns into the table above for the trend factor and trended ultimate losses.
AY OLEP ultimate
lossestrend
factortrended
ultimate
lossesultimate
losses
ratio2017 1,000 750 1.024 75% 2018 1,000 750 1.023 75% 2019 1,000 750 1.022 75% 2020 1,000 750 1.021 75% 2021 1,000 ? ECR = 75%