CAS Exam Errata

Update (1/10/26): We corrected some spelling/grammar typos in the study guide and reposted fresh copies of the outlines and study guide.

Study Guide & Review Videos

Friedland Ch. 10 (2/8/26) – On page 356, the last two columns in the table at the top were showing earned premium by mistake. They have been updated.

WM Ch. 5 (2/8/26) – On page 50, the final piece of RLG 4 in the picture at the bottom should say 0.75. On page 51, the formula for the area of RLG 4 should say 1 – 0.25 = 0.75.

WM Ch. 8 (1/31/26) – On page 121, the re-written indicated change formula should have a “-1” after it to represent a percentage change.

WM Ch. 9 (1/31/26) – On page 136, the PLR should say “1 – 0.30 – 0.05 = 0.65.”

WM Ch. 5 (1/27/26) – In the middle of page 60, under “Historical Period,” it should say 07/02/10 – 12/31/11.

WM Ch. 4 (1/13/26) – On the top of page 31, the in-force exposures should say 3.00.

WM Ch. 7 (1/10/26) – On page 103, the commission & brokerage example calculation should say 450/5000 – 1 = 9%. On page 110, the general expense dollar amount of 2015 should be $5.82.

Friedland Ch. 13 (1/10/26) – On page 419, for AYs 2003-2004, the final column should show 14,591 and 16,506, respectively.

Friedland Ch.14 (1/10/26) – On page 425, the definition of subrogation should say “…insurer’s right to recover the amount…”

Cookbook

Ratemaking – Aggregate Exposures – In step 4, policies E and F contribute to PY 2022, not 2021.

Practice Problems

Friedland Ch. 11 – F14 #17 (2/8/26) – We updated the solution to this problem to make it clear that we should be treating the latest diagonal as the base.

Update (1/5/26): Hi! As we were revising the accounting videos, we made some changes to the study guide to clarify some topics. Since those same changes impacted the flashcards, high-levels summaries, and essay problems, you will see similar changes throughout. Fresh copies of the study tools below have been posted to the course.

Study Guide & Review Videos

CFR Ch. 9 (1/25/26) – On page 193, the “gross paid-in & contributed surplus” line in the table should be labeled as “surplus adjustments” instead. Otherwise, you would need to calculate the change in that item when computing surplus.

CFR Ch. 8 (1/5/26) – On page 179, a few of the numbers in the bond discount example were slightly off. These were revised.

CFR Ch. 10 (1/5/26) – On page 219, the final two bullets under “Section I” needed to be merged (they are an “AND” condition). On page 218, under “Section C,” the ceding commissions noted here are specifically related to ceded UEPR.

CFR Ch. 13 (1/5/26) – On page 247, in the last use of Schedule T, the first line “Actuaries use this schedule to create a distribution…” should be removed.

CFR Ch. 18 (1/5/26) – On page 304, for the differences between Part 1 of the IEE and Part 3 of the U&IE, bullets 2 and 4 should be removed and replaced with “The IEE shows expenses on an incurred basis only whereas the U&IE also shows total expenses paid.”

CFR Ch. 19 (1/5/26) – On page 343, it should say “The R5 risk charge considers underwriting risk associated…”

CFR Ch. 22 (1/5/26) – On page 395, the GAAP discounting description was changed to be more clear that discounting is not generally allowed under GAAP.

CFR Ch. 25 (1/5/26) – On page 415, the example should say “Suppose the discounted best estimate of liabilities is $1.446M, with a risk margin of $0.041M.”

Cedar & Thompson (1/5/26) – On page 590, it should say “debt is $500 and equity is $2,000.”

Klann (1/5/26) – On page 654, the final bullet was revised to say “Difference in the discount factor (0.875 vs. 0.85)”

Practice Problems

CFR Ch. 9 (1/25/26) – On RF #1, the “gross paid-in & contributed surplus” line in the table should be labeled as “surplus adjustments” instead. Otherwise, you would need to calculate the change in that item when computing surplus.

CFR Ch. 10 (1/5/26) – Revised solution to essay problem #2 around Sections C and I.

CFR Ch. 13 (1/5/26) – Revised the final bullet in the solution to essay problem #7.

CFR Ch. 18 (1/5/26) – Revised the solution to essay problem #7a.

High-Level Summaries

CFR Ch. 13 (1/5/26) – Revised the final use of Schedule T

CFR Ch. 18 (1/5/26) – Revised the differences between Part I of the IEE and Part 3 of the U&IE

CFR Ch. 22 (1/5/26) – Revised loss reserve discounting to make it clear that it generally not allowed under GAAP

Flashcards

Horn & Webel (1/24/26) – The first “social goal” on flashcard 3 is not correct. It should say “Provide flood insurance to those otherwise unable to obtain it.”

CFR Ch. 10 (1/5/26) – Revised flashcard 2 to make it clear that Section C focuses on ceding commissions related to the ceded UEPR. Added Section I to flashcard 3

CFR Ch. 13 (1/5/26) – Revised final bullet of flashcard 8

CFR Ch. 18 (1/5/26) – On flashcard 16, revised the second way in which the IEE and U&IE differ.

Study Guide & Review Videos

Brosius (1/19/26) – On page 34, the formulas for E[(Q(X)-L(X))^2] and E[(Q(X)-a-bX)^2] should have the exponents within the expected value brackets, as shown here.

Practice Problems

Hurlimann EP #1 (2/7/26) – In the solution to part a., the “third” possible difference is not very clear. We went ahead and removed it.

Shapland S16 #12 (2/7/26) – In the solution to part b., the triangle should not say “fitted.” These are the actual incremental losses.

Study Guide & Review Videos

GLM Ch. 5 (2/8/26) – On page 94, the final bullet should say “the coefficient for the occupancy class = 4 and sprinkler = Yes interaction is positive and nearly offsets the main sprinkler effect.”

Mahler (1/23/26) – On page 23, there is an extra 0.6 in the method 4 prediction. It should say “(0.6/2)*0.023 + (0.6/2)*0.043 + (1-0.6)(0.025) = 0.0298.”

Flashcards

Fisher Ch. 3 (1/19/26) – On page 71 of the standard PDF, the title of the flashcard should say “Balance Equations (Per-Occurrence Limit).” On page 79 of the standard PDF, the title of the flashcard should say “Table L Savings.”

Cookbook

GLM – Partial and Working Residuals (1/20/26) – The linear predictor for Claim ID 7 should also include the 1.185 coefficient for FPC 4-9, resulting in a predicted value of 60,029. This has been corrected.”

Update (1/16/26): We updated all the study materials with the corrected Cummins Capital CAPM formula from the errata that is now on the content outline.

Study Guide & Review Videos

Mildenhall Ch. 10 (2/3/26) – On page 210, the definition of the shared liability should say “policyholders and investors both funds the assets in excess of the expected losses…”

Clark (1/30/26) – On page 52, the “pro-rata as to time” example is missing a factor to reflect the amount of the limit already exhausted by the loss. Hence, the number should be $2M(1.10)(4.5/10)(5/12) = $412,500.

Cummins Capital (1/20/26) – Per the official Cummins Capital errata posted with the Spring 2026 content outline, the formula for the LOB UW return on page 308 should be revised to “r_i = -(k_i/s_i)*r_f + beta_i(r_M – r_F).” Under the formula, the first bullet should say “Each LOB implicitly pays interest for the use of policyholder funds (-k_i/s_i)r_F.”

Using this formula, the returns at the top of page 310 should be r_1 = -0.4% and r_2 = 2.96%.” The combined ratios should be 100.4% and 0.70%.

Mildenhall Ch. 8 (1/19/26) – On page 192, under “Time t= 1,” the first bullet should say “investors receive after-tax UW profit of…and after-tax investment income…”

Mildenhall Ch. 5 (1/13/26) – On page 164, in the second to last bullet under “Law Invariant (LI),” it should say “Y models losses from a portfolio independent of E_1”

Clark (12/20/25) – On page 50, in the second bullet, the last number in the bracket should be 0.05, not 0.06. The calculated value of 0.056 is correct.

Cookbook

Mildenhall 1 – EPD Ratio Discrete Distribution (1/29/26) – The discussion section should say “The Expected Policyholder Deficit is also known as the Insolvency Put Option.”
Clark – Reinstatement Premium (1/5/26) – [PDF Version] In step 5, Reinstate Premium for loss 1 should be multiplied by 22/50, not 11/50. The Excel version and all answers are correct.

Practice Problems

Mildenhall 2 – Question 4 (1/29/26) – The question should have asked for investment leverage, not insurance leverage, since that is explicitly defined in Mildenhall

High-Level Summaries

No errata to report.

Flashcards

Mildenhall Ch. 14-15 (2/8/26) – On flashcard 12 of the standard PDF, the formula for total unit margin should be Pbar – Sbar. This is also mentioned in the official textbook errata.

Mildenhall Ch. 4 (1/23/26) – On flashcard 14 of the standard PDF, the second step should say “Find n so that n <= pN < (n+1).

Cummins Capital (1/20/26) – Per the official Cummins Capital errata posted with the Spring 2026 content outline, the formula for the LOB UW return on flashcard 7 (of the standard PDF) should be “r_i = -(k_i/s_i)*r_f + beta_i(r_M – r_F).” Accordingly, on flashcard 8, the first component should say “Each LOB implicitly pays interest for the use of policyholder funds (-k_i/s_i)r_F.”