Is There A New Way To Measure Fertilizer?

[ThomWV]

I am used to seeing fertilizer labled as 10-10-10, or 5-15-6 or whatever combination to signify the NPK percentages of the stuff. I have been looking at some on line in the last couple of days and I'm seeing something quite different a lot of times. Numbers like 0.5-2-1.5 or 2-.4-1.8 or some small numbers like that. Its almost as if they were ratios rather than expressions of actual content. Can anyone explain to me - in real simple terms - what the new version of the numbers means?

Sorry if this is way off the ususal track of questions here but I didn't know whereelse to find knowledable people, on line and willing to help and old fart who's been long out of school.