The mass distribution index of sporadic meteors and the indices of specific sporadic sources have been measured using data from 2007 to 2010 from the Canadian Meteor Orbit Radar. Single-station data from the 29.85-MHz system were used and the trends throughout the year are examined. We find that the average values for the sources are approximately equal, but the annual variation of each source is unique. We find that the overall average sporadic mass index is 2.17 ± 0.07, less than the frequently cited 2.34. The variation in the mass index throughout the year can provide information about the meteoroid populations that the Earth is encountering at different parts of its orbit.