There's absolutely nothing new about it - it's been like this for years and in every version of Excel I can remember. It generally happens when you've copied in stuff from other places, especially from text files which don't have the capacity to designate number or formula formats. In a text file, everything is text, even when it looks like a number or a formula. The default setting for every cell in every sheet in every book in Excel is "general" so if you start a sheet from scratch you shouldn't ever have this problem - which means that somebody must have copied in that "text" formatting, albeit unwittingly, at some point. Once you've changed one cell, though, you can copy it and it will take both the formula and the format with it, so you could, for instance, take what's in B16, copy it down to B24, paste it in and that will work fine from the moment you press the "paste" button.