Error Accounting in Electron Counting Experiments

Electron counting experiments attempt to provide a current of a known number of electrons per unit time. We propose architectures utilizing a few readily available electron-pumps or turnstiles with error rates of 1 part in $10^4$ with common sensitive electrometers to achieve the desireable accuracy of 1 part in $10^8$. This is achieved not by counting electrons but by counting the errors of individual devices; these are less frequent and therefore readily recognized and then accounted for. We thereby ease the route towards quantum based standards of current and capacitance.