Based on 10 years of European Incoherent Scatter (EISCAT) radar data, we have investigated the variation of ionospheric conductivities, electric fields, and currents over magnetic local time (MLT). Pedersen and Hall currents are generally enhanced especially on the nightside, and the MLT dependencies of these two types of ionospheric currents is similar, as previously found for field-aligned currents and auroral electrojets, respectively. We readdress the question to what extent the conductivity or the electric field contributes to the ionospheric current in different periods of MLT. On average, higher Pedersen conductivities are seen at 2000--0800 MLT in comparison with other MLT intervals, and these conductivities crucially contribute to Pedersen currents over two MLT sectors, around midnight and in the late morning. However, when the Pedersen current is stronger, not only the Pedersen conductivity but also the electric field becomes higher statistically on the nightside. Hall conductivities are also higher at about 2000--0800 MLT, showing two maxima, around midnight and in the late morning, and they increase more strongly than Pedersen conductivities on a statistical basis. Thus the nightside electrojets are mainly due to high Hall conductivities.