Jovian electron flux increases are observed by the University of Chicago experiment on the earth-orbiting satellite Imp 8 throughout five ~13-month Jovian synodic years during the period from launch of the satellite in late 1973 to 1979. A detailed analysis of these data is presented to define the characteristics of Jovian electron propagation to earth. Corotating interaction regins (CIR) that form at the leading edges of fast solar wind streams continue to modulate the propagation of MeV electrons from Jupiter to the orbit of earth to produce ~27-day recurrent variations in the Jovian electron flux density. Between these CIR's, both the spatial distribution of Jovian electrons around earth's orbit and the time-intensity profiles of the Jovian electron flux induced by the CIR modulation effect are shown to be consistent with the predictions of a simple diffusion model calculation, assuming that Jupiter's magnetosphere is a 'point' source of electrons. A new and significant result of this study is that these time-intensity profiles are more accurately described not by the assumption that Jupiter is a constant source of electrons, but rather by assuming that electron emission is initiated with each passage of a CIR by Jupiter with the emission continuing for several days only. A measurement of the spatial gradient of these electrons demonstrates that there is a significant reduction in the Jovian electron flux between Jupiter and earth even when earth is aligned with Jupiter along the average direction of the interplanetary magnetic field. This observation is inconsistent with 'scatter-free' propagation.