The main scale of this simulator is graduated in inch, that is subdivided in tenths.
In the dial, the pointer gives a complete turn (360°) every tenth of inch of avance (0.1in) and your display has one hundred divisions. This way, each mark that the pointer goes represent an advance of 0.1/100 of inch (one tenth divided by one hundred) or one thousandth of inch.
One advantage of adopting the dial to increase the caliper resolution, is that it allows the display to turn, after unlocked, to adjust the instrument and facilitate the inspection of tolerance of many peices without necessity of the interpretation one by one.
This instrument, as a rule, it can't substitute the micrometer in one thousandth of inch, because its accuracy (imprecision between presented value and the real) is bigger than the resolution one.
The resolution of monitor doesn't allow thta this virtual instrument interpolate each possibility of measure, if you wish to investigate this possibilities, interact with the simulator of dial indicator in one thousandth of inch and transfer what you have learned.