A method of time of flight (ToF) mass spectrometry comprising: pushing ions into a ToF mass analyser in a plurality of pushes, wherein the time spacing between adjacent pushes is shorter than either the longest flight time, or the range of flight times, of the ions; detecting the ions so as to obtain spectral data; decoding the spectral data to determine first mass spectral data relating to ions pushed into the ToF mass analyser by a first plurality of the pushes (P1-P4), and allocating this first mass spectral data to a first time stamp (t1); and decoding the spectral data to determine second mass spectral data relating to ions pushed into the ToF mass analyser by a second plurality of the pushes (P5-P8), and allocating this second mass spectral data to a second time-stamp (t2); wherein the first and second time-stamps have a time difference therebetween that is shorter than said longest flight time, or said range of flight times (4), in the ToF mass analyser.