A separate security deposits ledger arranged by sites, related programs, etc. shall be maintained for each project for the recording of security deposits. A separate security deposits ledger card or sheet shall be maintained for each apartment. This card shall be used to record both the receipt of the security deposit, its refund when the tenant vacates and the receipt of the security deposit from the new tenant. A specimen form of a security deposits ledger card is shown in Exhibit 10 of Appendix S-8. Each security deposits ledger sheet or card shall bear the tenants account number, address of the apartment, date security deposit was received and date refunded, tenants name and amount of the security deposit. The security deposits ledger is subsidiary to and shall be controlled by account 2114, Tenants Security Deposits. Prior to substantial completion, monthly trial balances of the security deposits ledger shall be taken, but thereafter the trial balances may be taken quarterly, inasmuch as the security deposits ledger will not ordinarily be very active once the project has been fully rented. Semiannually (as of September 30 and March 31), the total amount determined by multiplying the number of the dwelling units by the amount of the individual security deposit should be compared with the security deposit general ledger balance and the difference, if any, reconciled.