Market/sector breadth

It would be convenient to have a sense of the market and sector breadths, to figure out whether buying stocks in general, or buying stocks in a specific market sector is a good idea. This would help by knowing whether a sector is working against you, or whether the entire market is working against you.
I think market breadth would be the percentage of all stocks being tracked currently having either a bullish indicator (or perhaps more loosely, the ones having a green trend?), and sector breadth would be the same but in a specific sector?