A parallel fibre strand of 30 tex count is coming out from the nip of the front delivery rollers of a ring spinning machine. This strand is given twist to produce a yarn such that the length of the yarn becomes 0.95 times the length of the parallel fibre strand. If 600 turns are present in 1 m length of the yarn, then the twist factor (tpm-tex0.5) of the yarn (rounded off to the nearest integer) is____