"The amount of the surety that a private college or university submits pursuant to subsection (3) of this section is the greater of five thousand dollars or an amount equal to a reasonable estimate of the maximum prepaid, unearned tuition and fees of the institution for the period or term during the applicable academic year for which programs of instruction are offered including, but not limited to, programs offered on a semester, quarter, monthly, or class basis; except that the institution shall use the period or term of greatest duration and expense in determining this amount if the institution's academic year consists of one or more periods or terms. Following the initial filing of the surety with the department, the private college or university shall recalculate the amount of the surety annually based on a reasonable estimate of the maximum prepaid, unearned tuition and fees received by the institution for the applicable period or term."