I'm looking for a symbol/character that quickly conveys to the reader that the number that follows is to be understood as a decimal fraction in the range from 0 (minimum) to 1 (maximum). So for example "humidity: 0.4<symbol>" would represent the same idea as "humidity: 40%".
This would be analogous to the % (per cent) and ‰ (per mille) signs. When you read a table column labeled as "% humidity" or "% unemployment" you understand well and immediately that the numbers that follow below are relative to the range 0 to 100.
I want to use this in in table headers, function annotations, on UI buttons, as boilerplate text, and so forth. I.e. anywhere where there isn't a lot of space and it's better to be succinct. It would appear alongside other shorthands such as Σ for sum, ⌀ for average, Δ for difference, # for ordinal, etc.
For now I'm using the unit interval notation [0, 1] or [0...1] as a prefix or postfix but it's not always well understood.
I should mention that I'm unable to modify the data itself, so I can't just change 0.4 to 40% and use the percentage symbol instead.