# CAS Exam Errata

We always hated seeing errors in study material when taking exams, so we check everything as much as possible. If you do see a mistake, check out the up-to-date errata below for any corrections.

## Accidents Happen ...

If you spot an error in the study material, please send us a message so that we can correct the error and document it here for others.

## Errata by Exam

There are no errors to report so far for Spring 2024.

There are no errors to report so far for Spring 2024.

There are no errors to report so far for Spring 2024.

##### Exam 8 Cookbook

**Clark – Property Per Risk: Exposure Rating (9/29/23) – **In step 2, the example calculation should show a subscript of 100-250 for the Expected Reinsurer Loss.

##### Practice Exam

**Problem 13 (10/7/23) – **The 2023 version of the study kit no longer has some of the tables, so they would need to be given in the problem itself.

##### Practice Problem Bank

**Clark – 13 (10/7/23) – **Excess loss factors by definition can’t be greater than 1. Some of the given a and b parameters result in ELFs greater than 1. This is a mistake in the parameter values given. It doesn’t change the approach to solving the problem though. I will fix the values given in the problem for next sitting.

**NCCI Circular – 1 (10/7/23) – **The 2023 version of the study kit no longer has the two tables to look up the expected claim count group (ECG) based on the number of expected claims and subtable based on the per-occurrence excess ratio (k).

On an exam question, you would need to be given something similar to look up the correct ECG column and subtable. More likely they would just give you an excerpt from the appropriate column and subtable and skip the lookup.

Below are screenshots of those lookup tables so that you can see what they look like:

Expected Claim Count Group Lookup

**Bernegger – 2 (10/12/23) – **In the part b solution, the first and second derivatives of G(x) are incorrect. I updated the derivative calculations and uploaded the corrected version. The conclusion of part b that G(x) is a valid exposure curve is unchanged.

There is an alternate solution by using the formula:

E[x] = E[X/MPL] = 1 / G'(0)

This results in a different answer (~112,000). The reason for the inconsistency is that the values we have for gross premium and expected ceded loss aren’t internally consistent. I need to rework this problem a little with the values given. You should get the same MPL either way.

**Fisher – 11 (9/29/23) – **In the part a solution, the entry ratio label should say XS of 1.8 (not XS of 1.15). The calculation is correct.

**Grossi – 1 (7/8/23) – **Part a should also say that the AAL would increase with the higher hurricane loss. The files have been updated.

**Grossi – 9 (7/8/23) – **Similar to the example in Grossi (Table 5.1), all values in the table should be “per $1,000” of property value. The files have been updated.

##### Study Guide & Review Videos

**Clark (11/8/23) – **There is a typo on page 8. In the paragraph below the table, the second line should say “1.03^5 = 1.159,” not 1.086.

**Clark (11/12/23)** – There is a typo on page 34. In the fourth bullet of the Swing Plan example, the minimum premium should be 10%, not 15%.

**Clark (11/29/23) **– There is a typo on page 29. In the General Liability exposure rating example, it should say that “an actuary is pricing a **7.5M XS 2.5M **excess of loss treaty.” We will correct the video as well.

**Mildenhall Ch. 4 (12/1/23) **– On page 123, an extra row needs to be added at the bottom of the table in the example. When p = 0.9, VaR = 12, TVaR = 25, and CTE = 25. When p > 0.90, VaR = TVaR = CTE = 25.