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Example of Calculating a Firm's Premium Rate

An example of calculating the 2014 rates for a firm that is classified in risk class 4904-00, Clerical Office, N.O.C. with an experience factor of 0.9789.

Rate calculation
Accident Fund Base Rate $0.0301 (a)
Medical Aid Fund Base Rate $0.0225 (b)
Stay at Work Base Rate $0.0006 (c)
Accident + Medical Aid + Stay at Work Base Rate $0.0532 (d) = (a) + (b) + (c)
Firm's Experience Factor 0.9789 (e)
Firm's Accident + Medical + Stay at Work Experience Rate $0.0521 (f) = (d) × (e) rounded to four decimals
Supplemental Pension Rate $0.0910 (g)
Firm's Composite Rate $0.1431 (h) = (f) + (g)
Premium calculation assuming 1,000 hours worked
Premium $143.10 (i) = 1,000 × (h)
Employee portion of the rate
Firm's Employee Portion $0.0568 (j) = 0.5 × (b) × (e) + 0.5 × (c) × (e) + 0.5 × (g)

To calculate the premium rate:

  1. Add rows (a), (b), and (c) together to get row (d).
  2. Multiply row (d) by the firm's experience factor in row (e) and round the result to four decimal places to get row (f).
  3. Add row (f) and the Supplemental Pension rate in row (g) to get row (h) (the Supplemental Pension rate is not multiplied by the experience factor).

The workers' compensation premium paid to L&I is calculated by multiplying the Firm's Composite Rate in row (h), $0.1431 by the 1,000 hours worked which equals $143.10, in row (h).

The Employee Portion of the rate, which is withheld from the employee's wages for each hour worked, is calculated on row (j) is one half of the experience rated Medical Aid Fund rate plus one half of the experience rated Stay at Work rate plus one half of the Supplemental Pension Fund rate which equals $0.0568.

If this firm had more than one risk class, then a similar calculation would be done with each class.

If you need any help please contact your firm's Account Manager whose phone number is on your rate notice.

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