Ghost note (of Motown), Rocco Prestia (for Tower of Power), and Chuck Rainey (for Steely Dan, Aretha Franklin, and others) all include "tons of ghost notes done right" in their playing. In vocal music, especially in musical theater, a ghost note represents that the lyrics must be spoken rather than sung, retaining the marked rhythm but having indeterminate pitch. Notes with value less than a half note use an "X" instead of an oval as a note head. Occasionally a half note or whole note is represented with an open diamond note head, often representing a scream or grunt. As an extreme
Time value of money is to emphasize that "u" is a "parameter" (fixed in any instance—the time when the cash flow will occur), while "t" is a "variable" (time). In other words, future cash flows are exponentially discounted (exp) by the sum (integral, formula_44) of the future discount rates (formula_45 for future, "r"("v") for discount rates), while past cash flows are worth 0 (formula_46), because they have already occurred. Note that the value "at" the moment of a cash flow is not well-defined – there is a discontinuity at that point, and one can use a convention (assume cash flows have already occurred, or