(a) Definitions generally applicable to the Thrift Savings Plan are set forth at 5 CFR 1690.1.

(b) As used in this part:

Accrued means that income is accounted for when earned and expenses are accounted for when incurred.

Administrative expenses means expenses described in 5 U.S.C. 8437(c)(3).

Basis means the number of shares of an investment fund upon which the calculation of a share price is based.

Business day means any calendar day for which share prices are calculated.

Forfeitures means amounts forfeited to the TSP pursuant to 5 U.S.C. 8432(g)(2) and other non-statutory forfeited amounts, net of restored forfeited amounts.

Contributions, loan payments, loan disbursements, withdrawals, fund reallocations, fund transfers, and other transactions will be posted in dollars and in shares by source and by TSP core fund to the appropriate individual account by the TSP record keeper, using the share price for the date the transaction is posted.

(a) Each business day, net earnings will be calculated separately for each TSP core fund.

(b) Net earnings for each fund will equal:

(1) The sum of the following items, if any, accrued since the last business day:

(i) Interest on money of that fund which is invested in the Government Securities Investment Fund;

(ii) Interest on other short-term investments of the fund;

(iii) Other income (such as dividends, interest, or securities lending income) on investments of the fund; and

(iv) Capital gains or losses on investments of the fund, net of transaction costs.

(2) Minus the accrued administrative expenses of the fund, determined in accordance with § 1645.4.

(c) The net earnings for each TSP core fund determined in accordance with paragraph (b) of this section will be added to the residual net earnings for that fund from the previous business day, as described in § 1645.5(b), to produce the total net earnings. The total net earnings will be used to calculate the share price for that business day.

A portion of the administrative expenses accrued during each business day will be charged to each TSP core fund. A fund's respective portion of administrative expenses will be determined as follows:

(a) Accrued administrative expenses (other than those described in paragraph (b) of this section) will be reduced by:

(1) Accrued forfeitures;

(2) The fees described in §§ 1601.53(a) (relating to the mutual fund window), 1655.21 (relating to loans), 1653.6 (relating to retirement benefits court orders), and 1653.16 (relating to child support court orders) of this chapter; and

(3) Accrued earnings on forfeitures, abandoned accounts, unapplied deposits, and fees described in paragraph (a)(2) of this section.

(b) Investment management fees and other accrued administrative expenses attributable only to a particular fund will be charged solely to that fund.

(c) The amount of accrued administrative expenses not covered by forfeitures, fees, and earnings under paragraph (a) of this section, and not described in paragraph (b) of this section, will be charged on a pro rata basis to all TSP core funds, based on the respective fund balances on the last business day of the prior month end.

(a) Calculation of share price. The share price for each TSP core fund for each business day will apply to all sources of contributions for that fund. The total net earnings (as computed under § 1645.3) for each fund will be divided by the total fund basis (as computed under § 1645.6) for that fund. The resulting number, computed to ten decimal places, represents the incremental change in the value of that fund from the last business day to the current business day. The share price for that fund for the current business day is the sum of the incremental change in the share price for the current business day plus the share price for the prior business day, truncated to four decimal places.

(b) Residual net earnings. When the total net earnings for each business day for each TSP Fund are divided by the total fund basis in that fund, there will be residual net earnings attributable to the truncation described in paragraph (a) of this section which will not be included in the incremental change in the share price of the fund for that business day. The residual net earnings that are not included in the incremental share price for the fund may be added to the earnings for that fund on the next business day.

The total fund basis for a TSP core fund will be the sum of the number of shares in all individual accounts from all sources of contributions in that fund as of the opening of business on each business day.