5 CFR § 1645.1 - Definitions.

---
identifier: "/us/cfr/t5/s1645.1"
source: "ecfr"
legal_status: "authoritative_unofficial"
title: "5 CFR § 1645.1 - Definitions."
title_number: 5
title_name: "Administrative Personnel"
section_number: "1645.1"
section_name: "Definitions."
chapter_name: "FEDERAL RETIREMENT THRIFT INVESTMENT BOARD"
part_number: "1645"
part_name: "CALCULATION OF SHARE PRICES"
positive_law: false
currency: "2026-03-24"
last_updated: "2026-03-24"
format_version: "1.1.0"
generator: "[email protected]"
authority: "5 U.S.C. 8439(a)(3) and 8474."
regulatory_source: "68 FR 35502, June 13, 2003, unless otherwise noted."
cfr_part: "1645"
---


# 1645.1 Definitions.

(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.