I have never seen a DAW with that feature(?) -or for that matters, a beatfinder with decimal output
What song uses decimal in BPM?
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The version of Video Killed the Radio Star by the Buggles uses a decimal in the BPM if I recall correctly. Which isn't the song I'm currently working with, but I have confirmation from someone who's seen the project files for this song that the BPM does have a decimal value.
A lot of old songs use decimal BPM due to resamplings over the time.