tr_yield_curve: Daily treasury par yield curve rates
Description
This par yield curve, which relates the par yield on a security to its time to
maturity, is based on the closing market bid prices on the most recently auctioned
Treasury securities in the over-the-counter market. The par yields are derived from
input market prices, which are indicative quotations obtained by the Federal Reserve
Bank of New York at approximately 3:30 PM each business day.