  The thermodynamic uncertainty relation (TUR) is expected to hold in nanoscale
electronic conductors, when the electron transport process is quantum coherent
and the transmission probability is constant (energy and voltage independent).
We present measurements of the electron current and its noise in gold
atomic-scale junctions and confirm the validity of the TUR for electron
transport in realistic quantum coherent conductors. Furthermore, we show that
it is beneficial to present the current and its noise as a TUR ratio in order
to identify deviations from noninteracting-electron coherent dynamics.
