Detection statistics from a search of 99 days of Yellowknife Array data have been obtained. The mean 50 and 90 per cent cumulative detection levels are found to be m 3.9 and m 4.2 for the third zone from Yellowknife. Regional variations in the detection levels have been found. The 50 per cent cumulative detection level ranges from m 3.8 for Asia to m 4.3 for the Aleutians. Regional values of the slopes of the recurrence curves for log N versus magnitude have been obtained, the mean slope for the third zone from Yellowknife being −0.99.