An analytical workspace includes a set of data on which what-if analysis is performed, which is stored persistently and managed in a relational database system. By limiting baffles to a minimum number of positions necessary, fluctuations in the dot percent caused by reflected scattered light are suppressed, and a sufficient space needed for maintenance work on a spinner mirror and the like can be ensured. In addition, the clocked half-rail differential logic circuits are activated by a delayed clock and include a sense amplifier circuit that is triggered by a second delayed clock. The first axis and the second axis are offset relative to one another. The liquid volume may be displayed on the gauge itself or may be transmitted via telemetry to an external device.