BEGIN { size = -1 ; numFields = 0} /Bytes/ { if (numFields > 0) { avg = sum / numFields ; printf ("%d bytes avg %f us each\n", size, avg); } size = $1 ; numFields = 0 ; sum = 0; } /Slave/ { sum += $4 ; numFields++ ; } END { avg = sum / numFields ; printf ("%d bytes avg %f ms each\n", size, avg); }