The index base for an adjustment of the interest rate or time price differential is set by the index value on the first day of the month in which the credit document is dated.
Tex. Fin. Code § 347.103
RATE ADJUSTMENT INDEX BASE
Acts 1997, 75th Leg., ch. 1008, Sec. 1, eff
Official source: Texas Constitution and Statutes. Reproduced from public-domain Texas statutes; confirm against the official source for the current text. Not legal advice.