The term “earned premiums,” as used in sections 313 to 316¹ inclusive shall include gross premiums charged on all policies written, including all excess and additional premiums and reinsurance premiums accepted, less return premiums other than premiums returned to policyholders as dividends, and less all reinsurance premiums ceded and premiums on policies cancelled. Earned premiums attributable to any specific period shall be calculated by adding to the liability for unearned premiums at the beginning of the period, the premiums written during the period and subtracting the liability for unearned premiums at the end of the period.

The word “compensation” shall relate to all insurance effected by virtue of statutes providing compensation to employes for personal injuries irrespective of fault of the employer.

The word “liability” shall relate to all insurance except compensation insurance, against loss or damage from accident to or injuries suffered by an employe or other person and for which the insured is liable.

The terms “loss payments” and “loss expense payments” shall include all payments to claimants, including payments for medical and surgical attendance, legal expenses, salaries, and expenses of investigators, adjusters, and field men, rents, stationery, telegraph and telephone charges, postage, salaries, and expenses of office employes, home office expenses, and all other payments made on account of claims, whether such payments shall be allocated to specific claims or unallocated.

The term “monthly pro-rata basis” shall mean that calculation by which written premium becomes earned in even monthly amounts for each entire calendar month or part thereof during which a policy is in force, except that for the calendar months in which a premium is written or expires, one-half the even monthly amount is earned.

The term “even monthly amount” shall mean the written premium divided by the number of months for which the premium is written.