Is Keyword Difficulty tool algorithm changed ?

[trungbq06]

I'm very confused about this. From today, I realized that your algorithm for this tool changed. For example, I have search KC for this keyword before:

suitcases for kids has KC is 23.

But today I checked it again and it's 43. How can I deal with this new data? Is KC is good for determine that a keyword is easy to rank for ?

[JordanRailsback]

As far as I know, our algorithm for keyword difficulty has not been changed in any serious way. However, we did just release a fresh link index update, and since the difficulty is calculated based on a number of different link metrics, the scores that you're seeing could conceivably be differing due to these link metrics having been recalculated.

I'm honestly not sure what KC is, so I can't really speak to that, but perhaps someone else can swoop in and cover me on that one