Spreadsheets: you build them up with data points, make the rules by dropping down formulae, then watch them not make sense when an exception occurs. We can't help you with that, but maybe Google Sheets can make the interminable process more tolerable with its new context-aware formula suggestions.

All you have to do is plot a dataset, then start typing a formula in a cell for the suggestions to appear. You can accept each suggestion by pressing the Tab key as they increment from function to range points.

The feature can be turned off by hitting the ⋮ icon in the suggestion box or hitting the Tools menu, then Enable formula suggestions.

It began rolling out yesterday to all Google accounts. You'll see it within the next 2 weeks.