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While performing a physics experiment, measured data and final results are usually presented in a single table of results. The column headings of the table should contain both the quantity and the unit being measured or calculated.

As an example of accepted practice in column headings, if the quantity being measured is current in milliamperes, then I/mA would be the usual way to write the column heading. This convention follows the recommendations of the Symbols Committee of the Royal Society – the expression at the head of a column should be a dimensionless quantity. This is achieved by dividing the physical quantity by the unit in which it was measured.

The same convention is adopted to label the axes of a graph. Thus, the gradient and the y-intercept of a graph are mere numbers and have no units.