The estimated amount of day laborer contributions referred to in the preceding Article is the amount obtained by multiplying the amount calculated as specified by Order of the Ministry of Health, Labour and Welfare as the amount obtained by deducting an amount equivalent to insurance premiums relating to specially-insured day laborers in the relevant fiscal year from the prospective amount of expenses required for health insurance services in that fiscal year pertaining to specially-insured day laborers by the rate obtained by dividing the total number of days of payment of insurance premiums relating to specially-insured day laborers paid by the employer who established the day laborer health society in the previous fiscal year by the total number of days of payment of insurance premiums relating to specially-insured day laborers in that fiscal year.