If a business is experience rated, a completed Experience Rating Form (also referred to as an Experience Rating Worksheet, X-Mod Worksheet or ratesheet) is provided to its insurer when a policy is written. A completed ratesheet provides detailed information about the classification codes reported to the WCIRB, the payroll reported for each of those classifications, summaries of claims amounts and the experience modification.

Obtaining a ratesheet is the best way for a company to see the data that the WCIRB has on file. Typically, copies of this ratesheet are available by contacting your insurer or insurance professional. A policyholder may obtain a copy of its ratesheet once per year at no cost through the Experience Rating Worksheet Request. (Insurers, agents and brokers can sign up or log in to WCIRB Connect® to access ratesheets and inspection reports online. Refer to the Policyholder Data Products page for more information about ordering hard copies of ratesheets.)

Hover over a number in the image below to read more about that section of the ratesheet. Use the slider to see a comparison of the 2019 and 2018 versions of the form. You may need to wait a few seconds for the image to load.

Please note: The sample data in the form below is intended for demonstration purposes only.


This section of the ratesheet contains the information necessary to identify the employer, the insurer and policy and other infomation pertinent to the application of the experience modification.

  1. Bureau Assigned Classifications

    Appearing below the company name and address are the classifications (other than 8810, Clerical Office Employees, and 8742, Salespersons – outside) that have been assigned to the company by the WCIRB.

  2. Effective Date and Issue Date

    The effective date of the experience modification will normally correspond with the effective date of the policy. If, however, the employer's policies have not incepted on the same day every year, a correction to an experience modification has been issued or the operations are covered by more than one policy with different coverage dates, the effective date may differ from the policy inception date.

    The issue date is the date that the worksheet was originally released by the WCIRB to the insurance company.

  3. Insurer and Policy Information

    The ratesheet shows the insurer, insurer group, policy number and issuing office.

Summary of Payroll and Expected Losses

  1. Primary Threshold

    This is the maximum primary loss value used in the calculation. The Primary Threshold is determined based upon the total expected losses for the experience period. The Expected Loss Rates can be found in the Filings and Plans section of the WCIRB website.

  2. Policy Information

    Payroll and loss information on the worksheet is grouped by policy. The insurer code for the insurer that wrote the policy and the policy year is shown above the payroll and claims information for that policy. For information about the insurer codes used by the WCIRB, see WCIRB Insurer Codes

  3. Classification Code(s)

    The classifications listed on the ratesheet represent the operations of the business during the experience period.

  4. Payroll

    The ratesheet shows the payroll by classification code, reported for policies beginning within the experience period. Payroll is associated with the year in which your policy began, not necessarily the year in which it was paid. For example, for a policy that is in effect from December 31, 2015 to December 31, 2016, the payroll is reported for 2015, even though most of the payroll is paid in 2016.

  5. Expected Loss Rate

    The Expected Loss Rate reflects the anticipated average cost of benefits, per $100 of payroll, for a classification during the experience period. Expected Loss Rates are subject to change yearly. For example, the 2021 Expected Loss Rate for Classification 7219, Trucking Firms, is $3.31. In other words, for every $100 of payroll, the average cost of benefits resulting from workplace injuries assigned to Classification 7219 during the experience period was $3.31. The Expected Loss Rates table can be found in the California Workers' Compensation Experience Rating Plan—1995 (ERP).

  6. Expected Losses

    Expected Losses are determined by multiplying total payroll (per $100) for each classification by the Expected Loss Rate. This amount reflects an estimate of the cost of losses expected to arise during the experience period for your company based on the payroll reported for each classification.

  7. D-Ratio

    The Discount Ratio (D-Ratio) is the mechanism used to divide Expected Losses into Primary and Excess amounts. See "Expected Primary Losses" below. The difference between the D-Ratio for each classification reflects differences in the severity of claims by classification. In other words, the severity of the average claim for some classifications is significantly higher (indicating a more severe injury) than that of the average claim found in other classifications. There are over 90 different D-Ratios for each classification based upon the Primary Threshold. The D-Ratios is subject to change yearly. D-Ratios can be found in the Filings and Plans section of the WCIRB website.

  8. Expected Primary Losses

    Expected Primary Losses are determined by multiplying the Expected Losses for a classification by the D-Ratio for the classification. There are over 90 different D-Ratios for each classification based upon the Primary Threshold. Primary Expected Losses are totaled for all classifications and the difference between the Total Expected Losses and the Primary Expected Losses is the Expected Excess Losses.

  9. Expected Excess Losses

    The Expected Excess Losses is the difference between the total Expected Losses and the total Primary Expected Losses. This number represents average excess losses expected for similar-sized employers within your classification.

Summary of Claims and Actual Losses

  1. Claim Number

    This column shows the claim number(s) reported by the insurer. Each claim is to be individually listed for the policy period accordingly. 

  2. Injury Type

    This column shows the injury type codes assigned and reported by the insurer. This detail does not affect the experience modification calculation; it is for informational purposes only. Injury type codes are found in Part 4, Section V, B. Loss Data Elements, Rule 3 of the California Workers' Compensation Uniform Statistical Reporting Plan—1995.

    1. Death
    2. Permanent Total Disability
    3. Major Permanent Partial Disability
    4. Minor Permanent Partial Disability
    5. Temporary Total or Temporary Partial Disability
    6. Medical Only Claim
    7. Contract Medical or Hospital Allowances
    8. Compromised Death or "S" Claim
  3. Open/Closed

    This column indicates whether or not the claim was reported as Open or Closed when the claim was last valued. This detail does not affect the calculation. It is for informational purposes only.

  4. Actual Losses

    Actual Losses shows the total claims value (medical and indemnity) as of the last valuation date. For information about claim valuation dates, see Unit Statistical Reports. Actual Losses are totaled for all claims.

  5. Actual Primary Losses

    The total amount of the claim value up to the Primary Threshold is the Actual Primary Loss amount. (Any remaining amount is Excess.) Actual Primary Losses are totaled, and this figure is subtracted from the Actual Losses to determine the Actual Excess Losses.

  6. Experience Period Totals

    Various expected and actual loss columns are totaled. These amounts represent the totals for the experience period and will be used in the experience modification calculation.

  7. Experience Modification

    This is the experience modification that is the product of the experience rating calculation shown on the form. It is effective as of the Effective Date shown at the top of the worksheet.

  8. Loss-Free Rating

    The Loss-Free Rating is the experience modification that would have been calculated if $0 (zero) actual losses were incurred during the experience period. This hypothetical rating calculation is provided for informational purposes only.