Double whole note the "brevis" was to be considered the unit of time ("tactus"), instead of the usual "semibrevis". The old symbol , used as an alternative to the numerical proportion 2:1 in mensural notation, is carried over into modern notational practice to indicate a smaller relative value per note shape. It is normally used for music in a relatively quick tempo, where it indicates two minim (half note) beats in a bar of four crotchets (quarter notes), while is the equivalent of , with four crotchet beats . Double whole note In music, a double whole note (American), breve (international), or double
Value of time Value of time In transport economics, the value of time is the opportunity cost of the time that a traveler spends on his/her journey. In essence, this makes it the amount that a traveler would be willing to pay in order to save time, or the amount they would accept as compensation for lost time. One of the main justifications for transport improvements is the amount of time that travelers will save. Using a set of values of time, the economic benefits of a transport project can be quantified in order to compare them to the costs (thus forming the