Parsing and summing the list as float gives: 208505442949.07806, rounding this to 2 decimal places returns 208505442949.08, so obviously Excel and your verification program do use floats and therefore are inaccurate by design…
PS: I’ve heard there are still people using Excel to manage their money…
PPS: my iex session:
iex(3)> File.read!("MMR100.txt") |> String.split() |> Enum.map(&String.to_float/1) |> Enum.sum
208505442949.07806
iex(4)> File.read!("MMR100.txt") |> String.split() |> Enum.map(&String.to_float/1) |> Enum.sum |> Float.round(2)
208505442949.08
