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Not that fast, and it's pretty much in the US.
It seems that your prime ATM area of interest is Spain. According to CoinATMRadar, 2020 is practically flat in terms of Bitcoin ATMs during 2020 (70 currently listed, whilst there were 71 at the beginning of 2020):
https://coinatmradar.com/charts/growth/spain/Unfortunately, it will probably be extremely difficult to get some business like numbers here to understand the ROI behind this type of investment (it’s not very likely that those ATM owners are going to open-up and tell us much about their numbers, unless a franchise is willing to throw some information to pitch their business case upon direct query).